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Thirumurugan S, Ramanathan S, Muthiah KS, Lin YC, Hsiao M, Dhawan U, Wang AN, Liu WC, Liu X, Liao MY, Chung RJ. Inorganic nanoparticles for photothermal treatment of cancer. J Mater Chem B 2024; 12:3569-3593. [PMID: 38494982 DOI: 10.1039/d3tb02797j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
In recent years, inorganic nanoparticles (NPs) have attracted increasing attention as potential theranostic agents in the field of oncology. Photothermal therapy (PTT) is a minimally invasive technique that uses nanoparticles to produce heat from light to kill cancer cells. PTT requires two essential elements: a photothermal agent (PTA) and near-infrared (NIR) radiation. The role of PTAs is to absorb NIR, which subsequently triggers hyperthermia within cancer cells. By raising the temperature in the tumor microenvironment (TME), PTT causes damage to the cancer cells. Nanoparticles (NPs) are instrumental in PTT given that they facilitate the passive and active targeting of the PTA to the TME, making them crucial for the effectiveness of the treatment. In addition, specific targeting can be achieved through their enhanced permeation and retention effect. Thus, owing to their significant advantages, such as altering the morphology and surface characteristics of nanocarriers comprised of PTA, NPs have been exploited to facilitate tumor regression significantly. This review highlights the properties of PTAs, the mechanism of PTT, and the results obtained from the improved curative efficacy of PTT by utilizing NPs platforms.
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Affiliation(s)
- Senthilkumar Thirumurugan
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), No. 1, Sec. 3, Zhongxiao E. Rd, Taipei 10608, Taiwan.
| | - Susaritha Ramanathan
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), No. 1, Sec. 3, Zhongxiao E. Rd, Taipei 10608, Taiwan.
| | - Kayalvizhi Samuvel Muthiah
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), No. 1, Sec. 3, Zhongxiao E. Rd, Taipei 10608, Taiwan.
| | - Yu-Chien Lin
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), No. 1, Sec. 3, Zhongxiao E. Rd, Taipei 10608, Taiwan.
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
- Department and Graduate Institute of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Udesh Dhawan
- Centre for the Cellular Microenvironment, Division of Biomedical Engineering, James Watt School of Engineering, Mazumdar-Shaw Advanced Research Centre, University of Glasgow, Glasgow G116EW, UK
| | - An-Ni Wang
- Scrona AG, Grubenstrasse 9, 8045 Zürich, Switzerland
| | - Wai-Ching Liu
- Faculty of Science and Technology, Technological and Higher Education Institute of Hong Kong, New Territories, Hong Kong 999077, China
| | - Xinke Liu
- College of Materials Science and Engineering, Chinese Engineering and Research Institute of Microelectronics, Shenzhen University, Shenzhen 518060, China
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Mei-Yi Liao
- Department of Applied Chemistry, National Pingtung University, Pingtung 90003, Taiwan
| | - Ren-Jei Chung
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology (Taipei Tech), No. 1, Sec. 3, Zhongxiao E. Rd, Taipei 10608, Taiwan.
- High-value Biomaterials Research and Commercialization Center, National Taipei University of Technology (Taipei Tech), Taipei 106, Taiwan
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Effects of Pulsed Radiofrequency Source on Cardiac Ablation. Bioengineering (Basel) 2023; 10:bioengineering10020227. [PMID: 36829721 PMCID: PMC9952521 DOI: 10.3390/bioengineering10020227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/30/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
Heart arrhythmia is caused by abnormal electrical conduction through the myocardium, which in some cases, can be treated with heat. One of the challenges is to reduce temperature peaks-by still guaranteeing an efficient treatment where desired-to avoid any healthy tissue damage or any electrical issues within the device employed. A solution might be employing pulsed heat, in which thermal dose is given to the tissue with a variation in time. In this work, pulsed heat is used to modulate induced temperature fields during radiofrequency cardiac ablation. A three-dimensional model of the myocardium, catheter and blood flow is developed. Porous media, heat conduction and Navier-Stokes equations are, respectively, employed for each of the investigated domains. For the electric field, solved via Laplace equation, it is assumed that the electrode is at a fixed voltage. Pulsed heating effects are considered with a cosine time-variable pulsed function for the fixed voltage by constraining the product between this variable and time. Different dimensionless frequencies are considered and applied for different blood flow velocity and sustained voltages. Results are presented for different pulsed conditions to establish if a reasonable ablation zone, known from the obtained temperature profiles, can be obtained without any undesired temperature peaks.
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Yip WP, Kho ASK, Ooi EH, Ooi ET. An in silico assessment on the potential of using saline infusion to overcome non-confluent coagulation zone during two-probe, no-touch bipolar radiofrequency ablation of liver cancer. Med Eng Phys 2023; 112:103950. [PMID: 36842773 DOI: 10.1016/j.medengphy.2023.103950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/26/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
No-touch bipolar radiofrequency ablation (bRFA) is known to produce incomplete tumour ablation with a 'butterfly-shaped' coagulation zone when the interelectrode distance exceeds a certain threshold. Although non-confluent coagulation zone can be avoided by not implementing the no-touch mode, doing so exposes the patient to the risk of tumour track seeding. The present study investigates if prior infusion of saline into the tissue can overcome the issues of non-confluent or butterfly-shaped coagulation. A computational modelling approach based on the finite element method was carried out. A two-compartment model comprising the tumour that is surrounded by healthy liver tissue was developed. Three cases were considered; i) saline infusion into the tumour centre; ii) one-sided saline infusion outside the tumour; and iii) two-sided saline infusion outside the tumour. For each case, three different saline volumes were considered, i.e. 6, 14 and 22 ml. Saline concentration was set to 15% w/v. Numerical results showed that saline infusion into the tumour centre can overcome the butterfly-shaped coagulation only if the infusion volume is sufficient. On the other hand, one-sided infusion outside the tumour did not overcome this. Two-sided infusion outside the tumour produced confluent coagulation zone with the largest volume. Results obtained from the present study suggest that saline infusion, when carried out correctly, can be used to effectively eradicate liver cancer. This presents a practical solution to address non-confluent coagulation zone typical of that during two-probe bRFA treatment.
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Affiliation(s)
- Wai P Yip
- Mechanical Engineering Discipline, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Antony S K Kho
- Mechanical Engineering Discipline, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Ean H Ooi
- Mechanical Engineering Discipline, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, VIC 3350, Australia
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Radiofrequency ablation for liver tumors abutting complex blood vessel structures: treatment protocol optimization using response surface method and computer modeling. Int J Hyperthermia 2022; 39:733-742. [PMID: 35610101 DOI: 10.1080/02656736.2022.2075567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE To achieve a result of a large tumor ablation volume with minimal thermal damage to the surrounding blood vessels by designing a few clinically-adjustable operating parameters in radiofrequency ablation (RFA) for liver tumors abutting complex vascular structures. METHODS Response surface method (RSM) was employed to correlate the ablated tumor volume (Ra) and thermal damage to blood vessels (Dt) based on RFA operating parameters: ablation time, electrode position, and insertion angle. A coupled electric-thermal-fluid RFA computer model was created as the testbed for RSM to simulate RFA process. Then, an optimal RFA protocol for the two conflicting goals, namely (1) large tumor ablation and (2) small thermal damage to the surrounding blood vessels, has been achieved under a specific ablation environment. RESULTS Linear regression analysis confirmed that the RFA protocol significantly affected Ra and Dt (the adjusted coefficient of determination Radj2 = 93.61% and 95.03%, respectively). For a proposed liver tumor scenario (liver tumor with a dimension of 4×3×2.9 cm3 abutting a complex vascular structure), an optimized RFA protocol was found based on the regression results in RSM. Compared with a reference RFA protocol, in which the electrode was centered in the tumor with a 12-min ablation time, the optimized RFA protocol has increased Ra from 98.1% to 99.6% and decreased Dt from 4.1% to 0.4%, achieving nearly the complete ablation of proposed liver tumor and ignorable thermal damages to vessels. CONCLUSION This work showed that it is possible to design a few clinically-adjustable operating parameters of RFA for achieving a large tumor ablation volume while minimizing thermal damage to the surrounding blood vessels.
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Bühler L, Enderle MD, Kahn N, Polke M, Schneider MA, Heußel CP, Herth FJF, Linzenbold W. Establishment of a Tissue-Mimicking Surrogate for Pulmonary Lesions to Improve the Development of RFA Instruments and Algorithms. Biomedicines 2022; 10:biomedicines10051100. [PMID: 35625838 PMCID: PMC9138808 DOI: 10.3390/biomedicines10051100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/05/2022] [Accepted: 05/07/2022] [Indexed: 01/27/2023] Open
Abstract
(1) Development of radiofrequency ablation (RFA) systems for pulmonary lesions is restricted by availability of human tumor specimens and limited comparability of animal tissue. We aimed to develop a new surrogate tissue overcoming these drawbacks. (2) Reference values for electrical impedance in lung tumor tissue were collected during routine lung tumor RFA (n = 10). Subsequently, a tissue-mimicking surrogate with comparable electrical impedance and facilitating detection of the ablation margins was developed. (3) The mean electrical impedance for all patients was 103.5 ± 14.7 Ω. In the optimized surrogate tissue model consisting of 68% agar solution, 23% egg yolk, 9% thermochromic ink, and variable amounts of sodium chloride, the mean electrical impedance was adjustable from 74.3 ± 0.4 Ω to 183.2 ± 5.6 Ω and was a function (y = 368.4x + 175.2; R2 = 0.96; p < 0.001) of sodium chloride concentration (between 0 and 0.3%). The surrogate tissue achieved sufficient dimensional stability, and sample cuts revealed clear margins of color change for temperatures higher 60 °C. (4) The tissue-mimicking surrogate can be adapted to lung tumor with respect to its electrical properties. As the surrogate tissue allows for simple and cost-effective manufacturing, it is suitable for extensive laboratory testing of RFA systems for pulmonary ablation.
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Affiliation(s)
- Louisa Bühler
- Erbe Elektromedizin GmbH, 72072 Tübingen, Germany; (L.B.); (M.D.E.)
| | | | - Nicolas Kahn
- Department of Pneumology and Respiratory Care Medicine, Thoraxklinik at Heidelberg University Hospital, 69126 Heidelberg, Germany; (N.K.); (M.P.); (F.J.F.H.)
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), University of Heidelberg, 69120 Heidelberg, Germany; (M.A.S.); (C.P.H.)
| | - Markus Polke
- Department of Pneumology and Respiratory Care Medicine, Thoraxklinik at Heidelberg University Hospital, 69126 Heidelberg, Germany; (N.K.); (M.P.); (F.J.F.H.)
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), University of Heidelberg, 69120 Heidelberg, Germany; (M.A.S.); (C.P.H.)
| | - Marc A. Schneider
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), University of Heidelberg, 69120 Heidelberg, Germany; (M.A.S.); (C.P.H.)
- Translational Research Unit, Thoraxklinik at Heidelberg University Hospital, 69126 Heidelberg, Germany
| | - Claus Peter Heußel
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), University of Heidelberg, 69120 Heidelberg, Germany; (M.A.S.); (C.P.H.)
- Department of Diagnostic and Interventional Radiology, Heidelberg University Hospital, 69120 Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at Heidelberg University Hospital, 69126 Heidelberg, Germany
| | - Felix J. F. Herth
- Department of Pneumology and Respiratory Care Medicine, Thoraxklinik at Heidelberg University Hospital, 69126 Heidelberg, Germany; (N.K.); (M.P.); (F.J.F.H.)
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), University of Heidelberg, 69120 Heidelberg, Germany; (M.A.S.); (C.P.H.)
| | - Walter Linzenbold
- Erbe Elektromedizin GmbH, 72072 Tübingen, Germany; (L.B.); (M.D.E.)
- Correspondence: ; Tel.: +49-7071-755-2896
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A New Thermal Damage-Controlled Protocol for Thermal Ablation Modeled with Modified Porous Media-Based Bioheat Equation with Variable Porosity. Processes (Basel) 2022. [DOI: 10.3390/pr10020236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Thermal ablation of tumors is a minimally invasive technique more and more employed in cancer treatments. The main shortcomings of this technique are, on the one hand, the risk of an incomplete ablation, and on the other hand, the destruction of the surrounding healthy tissue. In this work, thermal ablation of a spherical hepatocellular carcinoma tumor (HCC) surrounded by healthy tissue is modeled. A modified porous media-based bioheat model is employed, including porosity variability from tumor core to healthy tissue, following experimental in vivo measures. Moreover, three different protocols are investigated: a constant heating protocol, a pulsating protocol, and a new developed damage-controlled protocol. The proposed damage-controlled protocol changes the heating source from constant to pulsating according to the thermal damage probability on the tumor rim. The equations are numerically solved by means of the commercial software COMSOL Multiphysics, and the outcomes show that the new proposed protocol is able to achieve the complete ablation in less time than the completely pulsating protocol, and to reach tissue temperature on the tumor rim 10 °C smaller than the constant protocol. These results are relevant to develop and improve different patient-based and automated protocols which can be embedded in medical devices’ software or in mobile applications, supporting medical staff with innovative technical solutions.
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Kho ASK, Ooi EH, Foo JJ, Ooi ET. How does saline backflow affect the treatment of saline-infused radiofrequency ablation? COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2021; 211:106436. [PMID: 34601185 DOI: 10.1016/j.cmpb.2021.106436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND OBJECTIVE Saline infusion is applied together with radiofrequency ablation (RFA) to enlarge the ablation zone. However, one of the issues with saline-infused RFA is backflow, which spreads saline along the insertion track. This raises the concern of not only thermally ablating the tissue within the backflow region, but also the loss of saline from the targeted tissue, which may affect the treatment efficacy. METHODS In the present study, 2D axisymmetric models were developed to investigate how saline backflow influence saline-infused RFA and whether the aforementioned concerns are warranted. Saline-infused RFA was described using the dual porosity-Joule heating model. The hydrodynamics of backflow was described using Poiseuille law by assuming the flow to be similar to that in a thin annulus. Backflow lengths of 3, 4.5, 6 and 9 cm were considered. RESULTS Results showed that there is no concern of thermally ablating the tissue in the backflow region. This is due to the Joule heating being inversely proportional to distance from the electrode to the fourth power. Results also indicated that larger backflow lengths led to larger growth of thermal damage along the backflow region and greater decrease in coagulation volume. Hence, backflow needs to be controlled to ensure an effective treatment of saline-infused RFA. CONCLUSIONS There is no risk of ablating tissues around the needle insertion track due to backflow. Instead, the risk of underablation as a result of the loss of saline due to backflow was found to be of greater concern.
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Affiliation(s)
- Antony S K Kho
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
| | - Ji J Foo
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, VIC 3350, Australia
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Unidirectional ablation minimizes unwanted thermal damage and promotes better thermal ablation efficacy in time-based switching bipolar radiofrequency ablation. Comput Biol Med 2021; 137:104832. [PMID: 34508975 DOI: 10.1016/j.compbiomed.2021.104832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 09/02/2021] [Accepted: 09/02/2021] [Indexed: 11/22/2022]
Abstract
Switching bipolar radiofrequency ablation (bRFA) is a thermal treatment modality used for liver cancer treatment that is capable of producing larger, more confluent and more regular thermal coagulation. When implemented in the no-touch mode, switching bRFA can prevent tumour track seeding; a medical phenomenon defined by the deposition of cancer cells along the insertion track. Nevertheless, the no-touch mode was found to yield significant unwanted thermal damage as a result of the electrodes' position outside the tumour. It is postulated that the unwanted thermal damage can be minimized if ablation can be directed such that it focuses only within the tumour domain. As it turns out, this can be achieved by partially insulating the active tip of the RF electrodes such that electric current flows in and out of the tissue only through the non-insulated section of the electrode. This concept is known as unidirectional ablation and has been shown to produce the desired effect in monopolar RFA. In this paper, computational models based on a well-established mathematical framework for modelling RFA was developed to investigate if unidirectional ablation can minimize unwanted thermal damage during time-based switching bRFA. From the numerical results, unidirectional ablation was shown to produce treatment efficacy of nearly 100%, while at the same time, minimizing the amount of unwanted thermal damage. Nevertheless, this effect was observed only when the switch interval of the time-based protocol was set to 50 s. An extended switch interval negated the benefits of unidirectional ablation.
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Comparisons between impedance-based and time-based switching bipolar radiofrequency ablation for the treatment of liver cancer. Comput Biol Med 2021; 134:104488. [PMID: 34020132 DOI: 10.1016/j.compbiomed.2021.104488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 01/19/2023]
Abstract
Switching bipolar radiofrequency ablation (bRFA) is a cancer treatment technique that activates multiple pairs of electrodes alternately based on a predefined criterion. Various criteria can be used to trigger the switch, such as time (ablation duration) and tissue impedance. In a recent study on time-based switching bRFA, it was determined that a shorter switch interval could produce better treatment outcome than when a longer switch interval was used, which reduces tissue charring and roll-off induced cooling. In this study, it was hypothesized that a more efficacious bRFA treatment can be attained by employing impedance-based switching. This is because ablation per pair can be maximized since there will be no interruption to RF energy delivery until roll-off occurs. This was investigated using a two-compartment 3D computational model. Results showed that impedance-based switching bRFA outperformed time-based switching when the switch interval of the latter is 100 s or higher. When compared to the time-based switching with switch interval of 50 s, the impedance-based model is inferior. It remains to be investigated whether the impedance-based protocol is better than the time-based protocol for a switch interval of 50 s due to the inverse relationship between ablation and treatment efficacies. It was suggested that the choice of impedance-based or time-based switching could ultimately be patient-dependent.
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Tucci C, Trujillo M, Berjano E, Iasiello M, Andreozzi A, Vanoli GP. Pennes' bioheat equation vs. porous media approach in computer modeling of radiofrequency tumor ablation. Sci Rep 2021; 11:5272. [PMID: 33674658 PMCID: PMC7970869 DOI: 10.1038/s41598-021-84546-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 02/15/2021] [Indexed: 12/28/2022] Open
Abstract
The objective of this study was to compare three different heat transfer models for radiofrequency ablation of in vivo liver tissue using a cooled electrode and three different voltage levels. The comparison was between the simplest but less realistic Pennes' equation and two porous media-based models, i.e. the Local Thermal Non-Equilibrium (LTNE) equations and Local Thermal Equilibrium (LTE) equation, both modified to take into account two-phase water vaporization (tissue and blood). Different blood volume fractions in liver were considered and the blood velocity was modeled to simulate a vascular network. Governing equations with the appropriate boundary conditions were solved with Comsol Multiphysics finite-element code. The results in terms of coagulation transverse diameters and temperature distributions at the end of the application showed significant differences, especially between Pennes and the modified LTNE and LTE models. The new modified porous media-based models covered the ranges found in the few in vivo experimental studies in the literature and they were closer to the published results with similar in vivo protocol. The outcomes highlight the importance of considering the three models in the future in order to improve thermal ablation protocols and devices and adapt the model to different organs and patient profiles.
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Affiliation(s)
- Claudio Tucci
- Dipartimento Di Medicina E Scienze Della Salute "Vincenzo Tiberio", Università del Molise, Via Francesco De Sanctis 1, 86100, Campobasso, Italy.
| | - Macarena Trujillo
- BioMIT, Department of Applied Mathematics, Universitat Politècnica de València, 46022, Camino de Vera, Valencia, Spain
| | - Enrique Berjano
- BioMIT, Department of Electronic Engineering, Universitat Politècnica de València, 46022, Camino de Vera, Valencia, Spain
| | - Marcello Iasiello
- Dipartimento Di Ingegneria Industriale, Università Degli Studi Di Napoli Federico II, P.le Tecchio 80, 80125, Napoli, Italy
| | - Assunta Andreozzi
- Dipartimento Di Ingegneria Industriale, Università Degli Studi Di Napoli Federico II, P.le Tecchio 80, 80125, Napoli, Italy
| | - Giuseppe Peter Vanoli
- Dipartimento Di Medicina E Scienze Della Salute "Vincenzo Tiberio", Università del Molise, Via Francesco De Sanctis 1, 86100, Campobasso, Italy
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Andreozzi A, Brunese L, Iasiello M, Tucci C, Vanoli GP. Numerical analysis of the pulsating heat source effects in a tumor tissue. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2021; 200:105887. [PMID: 33280933 DOI: 10.1016/j.cmpb.2020.105887] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND AND OBJECTIVES Hyperthermia treatment is nowadays recognized as the fourth additional cancer therapy technique following surgery, chemotherapy, and radiation; it is a minimally or non-invasive technique which involves fewer complications, a shorter hospital stay, and fewer costs. In this paper, pulsating heat effects on heat transfer in a tumor tissue under hyperthermia are analyzed. The objective of the paper is to find and quantify the advantages of pulsatile heat protocols under different periodical heating schemes and for different tissue morphologies. METHODS The tumor tissue is modeled as a porous sphere made up of a solid phase (tissue, interstitial space, etc.) and a fluid phase (blood). A Local Thermal Non-Equilibrium (LTNE) model is employed to consider the local temperature difference between the two phases. Governing equations with the appropriate boundary conditions are solved with the finite-element code COMSOL Multiphysics®. The pulsating effect is modeled with references to a cosine function with different frequencies, and such different heating protocols are compared at equal delivered energy, i. e. different heating times at equal maximum power. RESULTS Different tissue properties in terms of blood vessels sizes and blood volume fraction in tissue (porosity) are investigated. The results are shown in terms of tissue temperature and percentage of necrotic tissue obtained. The most powerful result achieved using a pulsating heat source instead of a constant one is the decreasing of maximum temperature in any considered case, even reaching about 30% lower maximum temperatures. Furthermore, the evaluation of tissue damage at the end of treatment shows that pulsating heat allows to necrotize the same tumoral tissue area of the non-pulsating heat source. CONCLUSIONS Modeling pulsating heat protocols in thermal ablation under different periodical heating schemes and considering different tissues morphologies in a tumor tissue highlights how the application of pulsating heat sources allows to avoid high temperature peaks, and simultaneously to ablate the same tumoral area obtained with a non-pulsating heat source. This is a powerful result to improve medical protocols and devices in thermal ablation of tumors.
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Affiliation(s)
- Assunta Andreozzi
- Dipartimento di Ingegneria Industriale, Università degli studi di Napoli Federico II, P.le Tecchio 80, 80125, Napoli, Italy
| | - Luca Brunese
- Dipartimento di Medicina e Scienze della Salute "Vincenzo Tiberio", Università del Molise, Via Francesco De Sanctis 1, 86100, Campobasso, ITALY
| | - Marcello Iasiello
- Dipartimento di Ingegneria Industriale, Università degli studi di Napoli Federico II, P.le Tecchio 80, 80125, Napoli, Italy
| | - Claudio Tucci
- Dipartimento di Medicina e Scienze della Salute "Vincenzo Tiberio", Università del Molise, Via Francesco De Sanctis 1, 86100, Campobasso, ITALY.
| | - Giuseppe Peter Vanoli
- Dipartimento di Medicina e Scienze della Salute "Vincenzo Tiberio", Università del Molise, Via Francesco De Sanctis 1, 86100, Campobasso, ITALY
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Yap S, Ooi EH, Foo JJ, Ooi ET. Bipolar radiofrequency ablation treatment of liver cancer employing monopolar needles: A comprehensive investigation on the efficacy of time-based switching. Comput Biol Med 2021; 131:104273. [PMID: 33631495 DOI: 10.1016/j.compbiomed.2021.104273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 12/16/2022]
Abstract
Radiofrequency ablation (RFA) is a thermal ablative treatment method that is commonly used to treat liver cancer. However, the thermal coagulation zone generated using the conventional RFA system can only successfully treat tumours up to 3 cm in diameter. Switching bipolar RFA has been proposed as a way to increase the thermal coagulation zone. Presently, the understanding of the underlying thermal processes that takes place during switching bipolar RFA remains limited. Hence, the objective of this study is to provide a comprehensive understanding on the thermal ablative effects of time-based switching bipolar RFA on liver tissue. Five switch intervals, namely 50, 100, 150, 200 and 300 s were investigated using a two-compartment 3D finite element model. The study was performed using two pairs of RF electrodes in a four-probe configuration, where the electrodes were alternated based on their respective switch interval. The physics employed in the present study were verified against experimental data from the literature. Results obtained show that using a shorter switch interval can improve the homogeneity of temperature distribution within the tissue and increase the rate of temperature rise by delaying the occurrence of roll-off. The coagulation volume obtained was the largest using switch interval of 50 s, followed by 100, 150, 200 and 300 s. The present study demonstrated that the transient thermal response of switching bipolar RFA can be improved by using shorter switch intervals.
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Affiliation(s)
- Shelley Yap
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
| | - Ji J Foo
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, VIC, 3350, Australia
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13
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Castro-López DL, Berjano E, Romero-Mendez R. Radiofrequency ablation combined with conductive fluid-based dopants (saline normal and colloidal gold): computer modeling and ex vivo experiments. Biomed Eng Online 2021; 20:4. [PMID: 33407532 PMCID: PMC7788784 DOI: 10.1186/s12938-020-00842-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 12/15/2020] [Indexed: 01/03/2023] Open
Abstract
Background The volume of the coagulation zones created during radiofrequency ablation (RFA) is limited by the appearance of roll-off. Doping the tissue with conductive fluids, e.g., gold nanoparticles (AuNPs) could enlarge these zones by delaying roll-off. Our goal was to characterize the electrical conductivity of a substrate doped with AuNPs in a computer modeling study and ex vivo experiments to investigate their effect on coagulation zone volumes. Methods The electrical conductivity of substrates doped with normal saline or AuNPs was assessed experimentally on agar phantoms. The computer models, built and solved on COMSOL Multiphysics, consisted of a cylindrical domain mimicking liver tissue and a spherical domain mimicking a doped zone with 2, 3 and 4 cm diameters. Ex vivo experiments were conducted on bovine liver fragments under three different conditions: non-doped tissue (ND Group), 2 mL of 0.9% NaCl (NaCl Group), and 2 mL of AuNPs 0.1 wt% (AuNPs Group). Results The theoretical analysis showed that adding normal saline or colloidal gold in concentrations lower than 10% only modifies the electrical conductivity of the doped substrate with practically no change in the thermal characteristics. The computer results showed a relationship between doped zone size and electrode length regarding the created coagulation zone. There was good agreement between the ex vivo and computational results in terms of transverse diameter of the coagulation zone. Conclusions Both the computer and ex vivo experiments showed that doping with AuNPs can enlarge the coagulation zone, especially the transverse diameter and hence enhance sphericity.
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Affiliation(s)
- Dora Luz Castro-López
- Facultad de Ingeniería, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP 78290, México
| | - Enrique Berjano
- BioMIT, Department of Electronic Engineering, Universitat Politècnica de València, 46018, Valencia, Spain
| | - Ricardo Romero-Mendez
- Facultad de Ingeniería, Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP 78290, México.
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14
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Role of saline concentration during saline-infused radiofrequency ablation: Observation of secondary Joule heating along the saline-tissue interface. Comput Biol Med 2020; 128:104112. [PMID: 33212331 DOI: 10.1016/j.compbiomed.2020.104112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/01/2020] [Accepted: 11/04/2020] [Indexed: 01/17/2023]
Abstract
Infusion of saline prior to radiofrequency ablation (RFA) is known to enlarge the thermal coagulation zone. The abundance of ions in saline elevate the electrical conductivity of the saline-saturated region. This promotes greater electric current flow inside the tissue, which increases the amount of RF energy deposition and subsequently enlarges the coagulation zone. In theory, infusion of higher concentration of saline should lead to larger coagulation zone due to the greater number of ions. Nevertheless, existing studies on the effects of concentration on saline-infused RFA have been conflicting, with the exact role of saline concentration yet to be fully elucidated. In this paper, computational models of saline-infused RFA were developed to investigate the role of saline concentration on the outcome of saline-infused RFA. The elevation in tissue electrical conductivity was modelled using the microscopic mixture model, while RFA was modelled using the coupled dual porosity-Joule heating model. Results obtained indicated that the presence of a concentration threshold to which no further elevation in tissue electrical conductivity and enlargement in thermal coagulation can occur. This threshold was determined to be at 15% NaCl. Analysis of the Joule heating distribution revealed the presence of a secondary Joule heating site located along the interface between wet and dry tissue. This secondary Joule heating was responsible for the enlargement in coagulation volume and its rapid growth phase during ablation.
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15
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Andreozzi A, Iasiello M, Netti PA. Effects of pulsating heat source on interstitial fluid transport in tumour tissues. J R Soc Interface 2020; 17:20200612. [PMID: 32993430 DOI: 10.1098/rsif.2020.0612] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Macromolecules and drug delivery to solid tumours is strongly influenced by fluid flow through interstitium, and pressure-induced tissue deformations can have a role in this. Recently, it has been shown that temperature-induced tissue deformation can influence interstitial fluid velocity and pressure fields, too. In this paper, the effect of modulating-heat strategies to influence interstitial fluid transport in tissues is analysed. The whole tumour tissue is modelled as a deformable porous material, where the solid phase is made up of the extracellular matrix and cells, while the fluid phase is the interstitial fluid that moves through the solid matrix driven by the fluid pressure gradient and vascular capillaries that are modelled as a uniformly interspersed fluid point-source. Pulsating-heat generation is modelled with a time-variable cosine function starting from a direct current approach to solve the voltage equation, for different pulsations. From the steady-state solution, a step-variation of vascular pressure included in the model equation as a mass source term via the Starling equation is simulated. Dimensionless 1D radial equations are numerically solved with a finite-element scheme. Results are presented in terms of temperature, volumetric strain, pressure and velocity profiles under different conditions. It is shown that a modulating-heat procedure influences velocity fields, that might have a consequence in terms of mass transport for macromolecules or drug delivery.
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Affiliation(s)
- A Andreozzi
- Dipartimento di Ingegneria Industriale (DII), Università degli Studi di Napoli Federico II, Piazzale Tecchio, 80, 80125 Napoli, Italy
| | - M Iasiello
- Dipartimento di Ingegneria Industriale (DII), Università degli Studi di Napoli Federico II, Piazzale Tecchio, 80, 80125 Napoli, Italy
| | - P A Netti
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università degli Studi di Napoli Federico II, Piazzale Tecchio, 80, 80125 Napoli, Italy
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16
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Cheong JKK, Ooi EH, Ooi ET. Thermal and thermal damage responses during switching bipolar radiofrequency ablation employing bipolar needles: A computational study on the effects of different electrode configuration, input voltage and ablation duration. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2020; 36:e3374. [PMID: 32519516 DOI: 10.1002/cnm.3374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/30/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Recent studies have demonstrated the effectiveness of switching bipolar radiofrequency ablation (bRFA) in treating liver cancer. Nevertheless, the clinical use of the treatment remains less common than conventional monopolar RFA - likely due to the lack of understanding of how the tissues respond thermally to the switching effect. The problem is exacerbated by the numerous possible switching combinations when bRFA is performed using bipolar needles, thus making theoretical deduction and experimental studies difficult. This article addresses this issue via computational modelling by examining if significant variation in the treatment outcome exists amongst six different electrode configurations defined by the X-, C-, U-, N-, Z- and O-models. Results indicated that the tissue thermal and thermal damage responses varied depending on the electrode configuration and the operating conditions (input voltage and ablation duration). For a spherical tumour, 30 mm in diameter, complete ablation could not be attained in all configurations with 70 V input voltage and 5 minutes ablation duration. Increasing the input voltage to 90 V enlarged the coagulation zone in the X-model only. With the other configurations, extending the ablation duration to 10 minutes was found to be the better at enlarging the coagulation zone.
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Affiliation(s)
- Jason K K Cheong
- School of Engineering, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Bandar Sunway, Malaysia
- Advanced Engineering Platform, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, Ballarat, Victoria, Australia
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17
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Tanaka T, Takata K, Kunimoto H, Fukuda H, Yamauchi R, Tsuchiya N, Inomata S, Yokoyama K, Morihara D, Takeyama Y, Shakado S, Sakisaka S, Hirai F. The Efficacy and Therapeutic Outcome of Bipolar Radiofrequency Ablation for the Treatment for Hepatocellular Carcinoma in the Real-World Setting, Compared with Monopolar Radiofrequency Ablation Conducted during the Same Period. Oncology 2020; 98:859-868. [PMID: 32799203 DOI: 10.1159/000508921] [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: 04/13/2020] [Accepted: 05/25/2020] [Indexed: 11/19/2022]
Abstract
BACKGROUND Several reports have suggested that the bipolar radiofrequency ablation (RFA) system is useful for the treatment of hepatocellular carcinoma (HCC). We evaluated the efficacy and safety of the bipolar RFA system for HCC treatment in the real-world setting. METHODS A total of 155 patients with 224 HCC tumors were enrolled. First, we examined the characteristics and outcomes of two RFA systems, monopolar and bipolar. Second, we identified the factors associated with local tumor progression in 72 patients with 104 HCC tumors, who could be followed up for at least 3 months after treatment and had been treated with the bipolar RFA system. RESULTS Of the baseline characteristics, tumor size and location were associated with the selection of the bipolar RFA system. A sufficient ablative zone margin (≥5 mm) was obtained by bipolar RFA in 81 of 94 (86.1%). The 1- and 2-year local tumor progression rates were 15.6 and 26.3%, respectively. An alpha-fetoprotein-L3 (AFP-L3) ratio >10% (HR: 7.64; 95% CI: 1.7-39.8, p = 0.007) and an insufficient ablative zone margin (<5 mm) (HR: 4.53; 95% CI: 1.02-20.3, p = 0.047) were related to local tumor progression in Cox regression analysis. Although severe adverse events were not observed in most cases, severe hepatic infarction occurred in 1 patient. CONCLUSIONS The bipolar RFA system is safe and effective for HCC treatment. Tumor localization within the liver is an important factor associated with bipolar RFA. Careful follow-up or reconsideration of treatment is necessary for cases with AFP-L3 ratio >10% or insufficient ablative zone margin (<5 mm), which were associated with local tumor progression.
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Affiliation(s)
- Takashi Tanaka
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan,
| | - Kazuhide Takata
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Hideo Kunimoto
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Hiromi Fukuda
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Ryo Yamauchi
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Naoaki Tsuchiya
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Shinjiro Inomata
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Keiji Yokoyama
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Daisuke Morihara
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Yasuaki Takeyama
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Satoshi Shakado
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Shotaro Sakisaka
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Fumihito Hirai
- Department of Gastroenterology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
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18
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Zheng Y, Zhang K, Zou J, Zou K, Sun J, Zhang A. An Noninvasive and Impedance-Ignored Control Strategy of the Ablation Zone in Radiofrequency Ablation Therapy. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:5514-5517. [PMID: 31947103 DOI: 10.1109/embc.2019.8857727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This study proposed a control strategy of the ablation margin using the temperature of the probe, without causing additional damage. Compared with other methods, the proposed strategy is real time and impedance-ignored, thus has a better performance in practice. A theoretical model was established to obtain the temperature distribution during the treatment. Several functions were obtained by fitting the results of the simulation model, with which a preset central temperature curve corresponding to a desired ablation zone was determined to regulate the temperature of the control point. Considering the various impedances in practice, a voltage adjustment method according to the error between the preset central temperature and the practical central temperature was proposed to minimize the effect of impedances. At last, the strategy was verified with phantom experiments. The results show that all the temperatures of the control points reached to 50°C at a specific time and kept for a while, which demonstrated the strategy had a good performance within the error range allowed.
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19
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Sano MB, Petrella RA, Kaufman JD, Fesmire CC, Xing L, Gerber D, Fogle CA. Electro-thermal therapy: Microsecond duration pulsed electric field tissue ablation with dynamic temperature control algorithms. Comput Biol Med 2020; 121:103807. [PMID: 32568680 DOI: 10.1016/j.compbiomed.2020.103807] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 04/27/2020] [Accepted: 05/02/2020] [Indexed: 12/13/2022]
Abstract
Electro-thermal therapy (ETT) is a new cancer treatment modality which combines the use of high voltage pulsed electric fields, dynamic energy delivery rates, and closed loop thermal control algorithms to rapidly and reproducibly create focal ablations. This study examines the ablative potential and profile of pulsed electric field treatments delivered in conjunction with precise temperature control algorithms. An ex vivo perfused liver model was utilized to demonstrate the capability of 5000 V 2 μs duration bipolar electrical pulses and dynamic temperature control algorithms to produce ablations. Using a three applicator array, 4 cm ablation zones were created in under 27 min. In this configuration, the algorithms were able to rapidly achieve and maintain temperatures of 80 °C at the tissue-electrode interface. A simplified single applicator and grounding pad approach was used to correlate the measured ablation zones to electric field isocontours in order to determine lethal electric field thresholds of 708 V/cm and 867 V/cm for 45 °C and 60 °C treatments, respectively. These results establish ETT as a viable method for hepatic tumor treatment with ablation profiles equivalent to other energy based techniques. The single applicator and multi-applicator approaches demonstrated may enable the treatment of complex tumor geometries. The flexibility of ETT temperature control yields a malleable intervention which gives clinicians robust control over the ablation modality, treatment time, and safety profile.
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Affiliation(s)
- Michael B Sano
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA.
| | - Ross A Petrella
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA
| | - Jacob D Kaufman
- UNC/ NCSU Joint Department of Biomedical Engineering, Raleigh, NC, USA
| | | | - Lei Xing
- Stanford University School of Medicine, Division of Radiation Physics, Stanford, CA, USA
| | - David Gerber
- Division of Abdominal Transplantation, Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Callie A Fogle
- Department of Clinical Sciences and Population Health & Pathobiology, North Carolina State University College of Veterinary Medicine, USA
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20
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Yap S, Cheong JKK, Ooi EH, Liao IY, Foo JJ, Nair SR, Mohd Ali AF. A numerical study on the no-touch bipolar radiofrequency ablation .. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:2887-2890. [PMID: 31946494 DOI: 10.1109/embc.2019.8857816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The commonly used radiofrequency ablation (RFA) technique for treating liver cancer is in the monopolar mode. This requires the insertion of the RF electrode directly into the tumor tissue, which increases the risks of tumor track seeding (TTS). One way to overcome TTS is by employing the bipolar RFA, implemented in the no-touch mode. In the no-touch mode, two RF electrodes are inserted into the healthy tissue that surrounds the tumor. The distance between the electrodes and the tumor is defined as the no-touch gap. The ability of the no-touch bipolar RFA to overcome TTS has been demonstrated in laboratory studies; however, little is known about the thermo-physiological responses of the tissue during the ablation process of the no-touch procedure. This will be investigated numerically in the present study. A 3D model of the liver tissue is developed and the no-touch bipolar RFA implemented using a pair of RF electrodes is simulated using the finite element method. In particular, the effects of the no-touch gap on the treatment outcome of the RFA procedure are investigated. Results show that a larger no-touch gap may result incomplete tumor destruction due to the central region of the tumor not being directly affected by the Joule heating phenomenon that is more prominent around the electrodes. This suggests that an improperly selected no-touch gap may result in a reduced efficiency of the no-touch bipolar RFA.
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21
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Radiofrequency ablation with four electrodes as a building block for matrix radiofrequency ablation: Ex vivo liver experiments and finite element method modelling. Influence of electric and activation mode on coagulation size and geometry. Surg Oncol 2020; 33:145-157. [PMID: 32561081 DOI: 10.1016/j.suronc.2020.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
Abstract
PURPOSE Radiofrequency ablation (RFA) is increasingly being used to treat unresectable liver tumors. Complete ablation of the tumor and a safety margin is necessary to prevent local recurrence. With current electrodes, size and shape of the ablation zone are highly variable leading to unsatisfactory local recurrence rates, especially for tumors >3 cm. In order to improve predictability, we recently developed a system with four simple electrodes with complete ablation in between the electrodes. This rather small but reliable ablation zone is considered as a building block for matrix radiofrequency ablation (MRFA). In the current study we explored the influence of the electric mode (monopolar or bipolar) and the activation mode (consecutive, simultaneous or switching) on the size and geometry of the ablation zone. MATERIALS AND METHODS The four electrode system was applied in ex vivo bovine liver. The electric and the activation mode were changed one by one, using constant power of 50 W in all experiments. Size and geometry of the ablation zone were measured. Finite element method (FEM) modelling of the experiment was performed. RESULTS In ex vivo liver, a complete and predictable coagulation zone of a 3 × 2 × 2 cm block was obtained most efficiently in the bipolar simultaneous mode due to the combination of the higher heating efficacy of the bipolar mode and the lower impedance by the simultaneous activation of four electrodes, as supported by the FEM simulation. CONCLUSIONS In ex vivo liver, the four electrode system used in a bipolar simultaneous mode offers the best perspectives as building block for MRFA. These results should be confirmed by in vivo experiments.
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Kho ASK, Foo JJ, Ooi ET, Ooi EH. Shape-shifting thermal coagulation zone during saline-infused radiofrequency ablation: A computational study on the effects of different infusion location. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 184:105289. [PMID: 31891903 DOI: 10.1016/j.cmpb.2019.105289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/07/2019] [Accepted: 12/19/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE The majority of the studies on radiofrequency ablation (RFA) have focused on enlarging the size of the coagulation zone. An aspect that is crucial but often overlooked is the shape of the coagulation zone. The shape is crucial because the majority of tumours are irregularly-shaped. In this paper, the ability to manipulate the shape of the coagulation zone following saline-infused RFA by altering the location of saline infusion is explored. METHODS A 3D model of the liver tissue was developed. Saline infusion was described using the dual porosity model, while RFA was described using the electrostatic and bioheat transfer equations. Three infusion locations were investigated, namely at the proximal end, the middle and the distal end of the electrode. Investigations were carried out numerically using the finite element method. RESULTS Results indicated that greater thermal coagulation was found in the region of tissue occupied by the saline bolus. Infusion at the middle of the electrode led to the largest coagulation volume followed by infusion at the proximal and distal ends. It was also found that the ability to delay roll-off, as commonly associated with saline-infused RFA, was true only for the case when infusion is carried out at the middle. When infused at the proximal and distal ends, the occurrence of roll-off was advanced. This may be due to the rapid and more intense heating experienced by the tissue when infusion is carried out at the electrode ends where Joule heating is dominant. CONCLUSION Altering the location of saline infusion can influence the shape of the coagulation zone following saline-infused RFA. The ability to 'shift' the coagulation zone to a desired location opens up great opportunities for the development of more precise saline-infused RFA treatment that targets specific regions within the tissue.
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Affiliation(s)
- Antony S K Kho
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia
| | - Ji J Foo
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, VIC 3350, Australia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia.
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23
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Andreozzi A, Iasiello M, Tucci C. An overview of mathematical models and modulated-heating protocols for thermal ablation. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/bs.aiht.2020.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Voizard N, Cerny M, Assad A, Billiard JS, Olivié D, Perreault P, Kielar A, Do RKG, Yokoo T, Sirlin CB, Tang A. Assessment of hepatocellular carcinoma treatment response with LI-RADS: a pictorial review. Insights Imaging 2019; 10:121. [PMID: 31853668 PMCID: PMC6920285 DOI: 10.1186/s13244-019-0801-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/26/2019] [Indexed: 02/07/2023] Open
Abstract
Computed tomography (CT) and magnetic resonance imaging (MRI) play critical roles for assessing treatment response of hepatocellular carcinoma (HCC) after locoregional therapy. Interpretation is challenging because posttreatment imaging findings depend on the type of treatment, magnitude of treatment response, time interval after treatment, and other factors. To help radiologists interpret and report treatment response in a clear, simple, and standardized manner, the Liver Imaging Reporting and Data System (LI-RADS) has developed a Treatment Response (LR-TR) algorithm. Introduced in 2017, the system provides criteria to categorize response of HCC to locoregional treatment (e.g., chemical ablation, energy-based ablation, transcatheter therapy, and radiation therapy). LR-TR categories include Nonevaluable, Nonviable, Equivocal, and Viable. LR-TR does not apply to patients on systemic therapies. This article reviews the LR-TR algorithm; discusses locoregional therapies for HCC, treatment concepts, and expected posttreatment findings; and illustrates LI-RADS treatment response assessment with CT and MRI.
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Affiliation(s)
- Nicolas Voizard
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada
| | - Milena Cerny
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Anis Assad
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada
| | - Jean-Sébastien Billiard
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada
| | - Damien Olivié
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada
| | - Pierre Perreault
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada
| | - Ania Kielar
- Joint Department of Medical Imaging, University of Toronto, Toronto, Canada
| | - Richard K G Do
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Takeshi Yokoo
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Claude B Sirlin
- Liver Imaging Group, Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - An Tang
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Québec, Canada. .,Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada. .,Department of Radiology, Radio-oncology and Nuclear Medicine, University of Montreal, Montreal, Canada.
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25
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Cheong JKK, Yap S, Ooi ET, Ooi EH. A computational model to investigate the influence of electrode lengths on the single probe bipolar radiofrequency ablation of the liver. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 176:17-32. [PMID: 31200904 DOI: 10.1016/j.cmpb.2019.04.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/14/2019] [Accepted: 04/25/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND OBJECTIVES Recently, there have been calls for RFA to be implemented in the bipolar mode for cancer treatment due to the benefits it offers over the monopolar mode. These include the ability to prevent skin burns at the grounding pad and to avoid tumour track seeding. The usage of bipolar RFA in clinical practice remains uncommon however, as not many research studies have been carried out on bipolar RFA. As such, there is still uncertainty in understanding the effects of the different RF probe configurations on the treatment outcome of RFA. This paper demonstrates that the electrode lengths have a strong influence on the mechanics of bipolar RFA. The information obtained here may lead to further optimization of the system for subsequent uses in the hospitals. METHODS A 2D model in the axisymmetric coordinates was developed to simulate the electro-thermophysiological responses of the tissue during a single probe bipolar RFA. Two different probe configurations were considered, namely the configuration where the active electrode is longer than the ground and the configuration where the ground electrode is longer than the active. The mathematical model was first verified with an existing experimental study found in the literature. RESULTS Results from the simulations showed that heating is confined only to the region around the shorter electrode, regardless of whether the shorter electrode is the active or the ground. Consequently, thermal coagulation also occurs in the region surrounding the shorter electrode. This opened up the possibility for a better customized treatment through the development of RF probes with adjustable electrode lengths. CONCLUSIONS The electrode length was found to play a significant role on the outcome of single probe bipolar RFA. In particular, the length of the shorter electrode becomes the limiting factor that influences the mechanics of single probe bipolar RFA. Results from this study can be used to further develop and optimize bipolar RFA as an effective and reliable cancer treatment technique.
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Affiliation(s)
- Jason K K Cheong
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia
| | - Shelley Yap
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia
| | - Ean T Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, VIC 3350, Australia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia.
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Ooi EH, Lee KW, Yap S, Khattab MA, Liao IY, Ooi ET, Foo JJ, Nair SR, Mohd Ali AF. The effects of electrical and thermal boundary condition on the simulation of radiofrequency ablation of liver cancer for tumours located near to the liver boundary. Comput Biol Med 2019; 106:12-23. [DOI: 10.1016/j.compbiomed.2019.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/04/2019] [Accepted: 01/05/2019] [Indexed: 01/12/2023]
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Barnat N, Grisey A, Lecuelle B, Anquez J, Gerold B, Yon S, Aubry JF. Noninvasive vascular occlusion with HIFU for venous insufficiency treatment: preclinical feasibility experience in rabbits. ACTA ACUST UNITED AC 2019; 64:025003. [DOI: 10.1088/1361-6560/aaf58d] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Zhang B, Yang Y, Ding L, Moser MAJ, Zhang EM, Zhang W. Tumor Ablation Enhancement by Combining Radiofrequency Ablation and Irreversible Electroporation: An In Vitro 3D Tumor Study. Ann Biomed Eng 2018; 47:694-705. [PMID: 30565007 DOI: 10.1007/s10439-018-02185-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 12/06/2018] [Indexed: 02/08/2023]
Abstract
We hypothesized and demonstrated for the first time that significant tumor ablation enhancement can be achieved by combining radiofrequency ablation (RFA) and irreversible electroporation (IRE) using a 3D cervical cancer cell model. Three RFA (43, 50, and 60 °C for 2 min) and IRE protocols (350, 700, and 1050 V/cm) were used to study the combining effect in the 3D tumor cell model. The in vitro experiment showed that both RFA enhanced IRE and IRE enhanced RFA can lead to a significant increase in the size of the ablation zone compared to IRE and RFA alone. It was also noted that the sequence of applying ablation energy (RFA → RE or IRE → RFA) affected the efficacy of tumor ablation enhancement. The electrical conductivity of 3D tumor was found to be increased after preliminary RFA or IRE treatment. This increase in tumor conductivity may explain the enhancement of tumor ablation. Another explanation might be that there is repeat injury to the transitional zone of the first treatment by the second one. The promising results achieved in the study can provide us useful clues about the treatment of large tumors abutting large vessels or bile ducts.
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Affiliation(s)
- Bing Zhang
- Tumor Ablation Group, Biomedical Science and Technology Research Center, School of Mechatronic Engineering and Automation, Shanghai University, 99 Shangda Road, Baoshan, Shanghai, 200444, China.
| | - Yongji Yang
- School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Lujia Ding
- School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Michael A J Moser
- Department of Surgery, University of Saskatchewan, Saskatoon, SK, S7N 0W8, Canada
| | - Edwin M Zhang
- Division of Vascular & Interventional Radiology, Department of Medical Imaging, University of Toronto, Toronto, ON, M5T 1W7, Canada
| | - Wenjun Zhang
- Tumor Ablation Group, Biomedical Science and Technology Research Center, School of Mechatronic Engineering and Automation, Shanghai University, 99 Shangda Road, Baoshan, Shanghai, 200444, China.,Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK, S7N 5A9, Canada
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Ooi EH, J. Y. Chia N, Ooi ET, Foo JJ, Liao IY, R. Nair S, Mohd Ali AF. Comparison between single- and dual-porosity models for fluid transport in predicting lesion volume following saline-infused radiofrequency ablation. Int J Hyperthermia 2018; 34:1142-1156. [DOI: 10.1080/02656736.2018.1437282] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Ean H. Ooi
- School of Engineering, Monash University Malaysia, Selangor, Malaysia
- Advanced Engineering Platform, Monash University Malaysia, Selangor, Malaysia
| | | | - Ean T. Ooi
- School of Engineering and Information Technology, Faculty of Science and Technology, Federation University, Ballarat, VIC, Australia
| | - Ji J. Foo
- School of Engineering, Monash University Malaysia, Selangor, Malaysia
| | - Iman Y. Liao
- School of Computer Science, University of Nottingham Malaysia Campus, Selangor, Malaysia
| | - Shalini R. Nair
- Department of Radiology, National Cancer Institute, Putrajaya, Malaysia
| | - Ahmad F. Mohd Ali
- Department of Radiology, National Cancer Institute, Putrajaya, Malaysia
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Chang W, Lee JM, Lee DH, Yoon JH, Kim YJ, Yoon JH, Han JK. Comparison of switching bipolar ablation with multiple cooled wet electrodes and switching monopolar ablation with separable clustered electrode in treatment of small hepatocellular carcinoma: A randomized controlled trial. PLoS One 2018; 13:e0192173. [PMID: 29420589 PMCID: PMC5805261 DOI: 10.1371/journal.pone.0192173] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 01/16/2018] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE A randomized controlled trial was conducted to prospectively compare the therapeutic effectiveness of switching bipolar (SB) radiofrequency ablation (RFA) using cooled-wet electrodes and switching monopolar (SM) RFA using separable clustered (SC) electrodes in patients with hepatocellular carcinomas (HCCs). MATERIALS AND METHODS This prospective study was approved by our Institutional Review Board. Between April 2014 and January 2015, sixty-nine patients with 74 HCCs were randomly treated with RFA using either internally cooled-wet (ICW) electrodes in SB mode (SB-RFA, n = 36) or SC electrodes in SM mode (SM-RFA, n = 38). Technical parameters including the number of ablations, ablation time, volume, energy delivery, and complications were evaluated. Thereafter, 1-year and 2-year local tumor progression (LTP) free survival rates were compared between the two groups using the Kaplan-Meier method. RESULTS In the SB-RFA group, less number of ablations were required (1.72±0.70 vs. 2.31±1.37, P = 0.039), the ablation time was shorter (10.9±3.9 vs.14.3±5.0 min, p = 0.004), and energy delivery was smaller (13.1±6.3 vs.23.4±12.8 kcal, p<0.001) compared to SM-RFA. Ablation volume was not significantly different between SB-RFA and SM-RFA groups (61.8±24.3 vs.54.9±23.7 cm3, p = 0.229). Technical failure occurred in one patient in the SM-RFA group, and major complications occurred in one patient in each group. The 1-year and 2-year LTP free survival rates were 93.9% and 84.3% in the SB-RFA group and 94.4% and 88.4% in the SM-RFA group (p = 0.687). CONCLUSION Both SB-RFA using ICW electrodes and SM-RFA using SC electrodes provided comparable LTP free survival rates although SB-RFA required less ablations and shorter ablation time.
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Affiliation(s)
- Won Chang
- Department of Radiology, Seoul National University Bundang Hospital, 82, Gumi-ro 173 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Jeong Min Lee
- Department of Radiology, Seoul National University Hospital, Jongno-gu, Seoul, Korea
- Seoul National University College of Medicine, Jongno-gu, Seou, Korea
- * E-mail:
| | - Dong Ho Lee
- Department of Radiology, Seoul National University Hospital, Jongno-gu, Seoul, Korea
| | - Jeong Hee Yoon
- Department of Radiology, Seoul National University Hospital, Jongno-gu, Seoul, Korea
| | - Yoon Jun Kim
- Seoul National University College of Medicine, Jongno-gu, Seou, Korea
- Department of Internal Medicine, Seoul National University Hospital, Jongno-gu, Seoul, Korea
| | - Jung Hwan Yoon
- Seoul National University College of Medicine, Jongno-gu, Seou, Korea
- Department of Internal Medicine, Seoul National University Hospital, Jongno-gu, Seoul, Korea
| | - Joon Koo Han
- Department of Radiology, Seoul National University Hospital, Jongno-gu, Seoul, Korea
- Seoul National University College of Medicine, Jongno-gu, Seou, Korea
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Irastorza RM, Trujillo M, Berjano E. How coagulation zone size is underestimated in computer modeling of RF ablation by ignoring the cooling phase just after RF power is switched off. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:e2869. [PMID: 28146314 DOI: 10.1002/cnm.2869] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/29/2017] [Indexed: 06/06/2023]
Abstract
All the numerical models developed for radiofrequency ablation so far have ignored the possible effect of the cooling phase (just after radiofrequency power is switched off) on the dimensions of the coagulation zone. Our objective was thus to quantify the differences in the minor radius of the coagulation zone computed by including and ignoring the cooling phase. We built models of RF tumor ablation with 2 needle-like electrodes: a dry electrode (5 mm long and 17G in diameter) with a constant temperature protocol (70°C) and a cooled electrode (30 mm long and 17G in diameter) with a protocol of impedance control. We observed that the computed coagulation zone dimensions were always underestimated when the cooling phase was ignored. The mean values of the differences computed along the electrode axis were always lower than 0.15 mm for the dry electrode and 1.5 mm for the cooled electrode, which implied a value lower than 5% of the minor radius of the coagulation zone (which was 3 mm for the dry electrode and 30 mm for the cooled electrode). The underestimation was found to be dependent on the tissue characteristics: being more marked for higher values of specific heat and blood perfusion and less marked for higher values of thermal conductivity.
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Affiliation(s)
- Ramiro M Irastorza
- Instituto de Física de Líquidos y Sistemas Biológicos (CONICET), Calle 59 No 789, B1900BTE, La Plata, Argentina
- Instituto de Ingeniería y Agronomía, Universidad Nacional Arturo Jauretche, Avenida Calchaquí No 6200, 1888, Florencio Varela, Argentina
| | - Macarena Trujillo
- Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Camí de Vera, 46022, València, Spain
| | - Enrique Berjano
- Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València, Camí de Vera, 46022, València, Spain
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McCarthy CJ, Gervais DA. Decision Making: Thermal Ablation Options for Small Renal Masses. Semin Intervent Radiol 2017; 34:167-175. [PMID: 28579684 DOI: 10.1055/s-0037-1602708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Renal cell carcinoma is a relatively common tumor, with an estimated 63,000 new cases being diagnosed in the United States in 2016. Surgery, be it with partial or total nephrectomy, is considered the mainstay of treatment for many patients. However, those patients with small renal masses, typically less than 3 to 4 cm in size who are deemed unsuitable for surgery, may be suitable for percutaneous thermal ablation. We review the various treatment modalities, including radiofrequency ablation, microwave ablation, and cryoablation; discuss the advantages and disadvantages of each method; and review the latest data concerning the performance of the various ablative modalities compared with each other, and compared with surgery.
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Affiliation(s)
- Colin J McCarthy
- Division of Abdominal Imaging, Massachusetts General Hospital, Boston, Massachusetts
| | - Debra A Gervais
- Division of Abdominal Imaging, Massachusetts General Hospital, Boston, Massachusetts
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Trujillo M, Bon J, Berjano E. Computational modelling of internally cooled wet (ICW) electrodes for radiofrequency ablation: impact of rehydration, thermal convection and electrical conductivity. Int J Hyperthermia 2017; 33:624-634. [DOI: 10.1080/02656736.2017.1303751] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Macarena Trujillo
- Biomedical Synergy, Department of Applied Mathematics, Universitat Politècnica de València, Valencia, Spain
| | - Jose Bon
- Food Technology Department, Universitat Politècnica de València, Valencia, Spain
| | - Enrique Berjano
- Biomedical Synergy, Department of Electronic Engineering, Universitat Politècnica de València, Valencia, Spain
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Yan S, Wu X, Wang W. Theoretical and experimental analysis of amplitude control ablation and bipolar ablation in creating linear lesion and discrete lesions for treating atrial fibrillation. Int J Hyperthermia 2017; 33:608-616. [DOI: 10.1080/02656736.2017.1286390] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Shengjie Yan
- Electronic Engineering Department, Fudan University, Shanghai, China
| | - Xiaomei Wu
- Electronic Engineering Department, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Assistive Devices, Shanghai, China
- Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention (MICCAI) of Shanghai, Fudan University, Shanghai, China
| | - Weiqi Wang
- Electronic Engineering Department, Fudan University, Shanghai, China
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Zhang B, Moser MAJ, Zhang EM, Luo Y, Zhang W. A new approach to feedback control of radiofrequency ablation systems for large coagulation zones. Int J Hyperthermia 2016; 33:367-377. [DOI: 10.1080/02656736.2016.1263365] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Affiliation(s)
- Bing Zhang
- CISR Lab, East China University of Science and Technology, Shanghai, China
- Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Canada
| | | | - Edwin M. Zhang
- Division of Vascular & Interventional Radiology, Department of Medical Imaging, University of Toronto, Toronto, Canada
| | - Yigang Luo
- Department of Surgery, University of Saskatchewan, Saskatoon, Canada
| | - Wenjun Zhang
- CISR Lab, East China University of Science and Technology, Shanghai, China
- Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Canada
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Canada
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Zhao W, Chen JZ, Hu JH, Huang JQ, Jiang YN, Luo G, Yi GF, Peng ZH, Wang H, Shen J, Gao BL. In vivo effects of radiofrequency ablation on long bones and the repair process in swine models. Jpn J Radiol 2016; 35:31-39. [PMID: 27822778 DOI: 10.1007/s11604-016-0596-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 10/21/2016] [Indexed: 12/20/2022]
Abstract
PURPOSE To investigate in vivo effect of radiofrequency ablation (RFA) on swine long bones and the repair process. MATERIALS AND METHODS RFA was performed in six swine at the end and middle part of the tibia or femur. After RFA, radiological examinations were performed, and the swine were killed immediately and at different time points post-RFA for histopathological examination. RESULTS All swine had successful RFA. The RFA-induced elliptical necrotic area ranged from 3.81-5.24 cm2 (mean 4.08 ± 0.73 cm2) at the bone end but 5.60-8.98 cm2 (mean 7.58 ± 1.41) at the middle part immediately after RFA until 10 days, with the necrosis area significantly smaller (P = 0.000) at the end than at the middle. RFA only damaged the cortical bone slightly (0.01 cm thick) with no damage to the soft tissues outside the compact bone at both the end and middle. Surrounding the elliptic pale zone of coagulative necrosis was a narrow brown band of hemorrhage and inflammatory exudate. From day 10 until week 12, tissue proliferation and repair became increasingly apparent, with proliferated granulation, fibrous tissue, and fresh and mature bone trabecula. CONCLUSION RFA can quickly and effectively destroy the cancellous bone tissue without affecting the cortical bone and activate bone remodeling.
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Affiliation(s)
- Wei Zhao
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Jin-Zhou Chen
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Ji-Hong Hu
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Jian-Qiang Huang
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Yong-Neng Jiang
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Gang Luo
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Gen-Fa Yi
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Zhao-Hong Peng
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Hui Wang
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Jin Shen
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China
| | - Bu-Lang Gao
- Department of Medical Imaging, The First Affiliated Hospital, Kunming Medical University, 295 Xichang Road, Kunming, Yunnan, 650032, People's Republic of China.
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Trujillo M, Bon J, José Rivera M, Burdío F, Berjano E. Computer modelling of an impedance-controlled pulsing protocol for RF tumour ablation with a cooled electrode. Int J Hyperthermia 2016; 32:931-939. [PMID: 27452352 DOI: 10.1080/02656736.2016.1190868] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To develop computer models to mimic the impedance-controlled pulsing protocol implemented in radiofrequency (RF) generators used for clinical practice of radiofrequency ablation (RFA), and to assess the appropriateness of the models by comparing the computer results with those obtained in previous experimental studies. METHODS A 12-min RFA was modelled using a cooled electrode (17G, 3 cm tip) inserted in hepatic tissue. The short (transverse) diameter of the coagulation zone was assessed under in vivo (with blood perfusion (BP) and considering clamping) and ex vivo (at 21 °C) conditions. The computer results obtained by programming voltage pulses were compared with current pulses. RESULTS The differences between voltage and current pulses were noticeable: using current instead of voltage allows larger coagulation zones to be created, due to the higher energy applied by current pulses. If voltage pulses are employed the model can accurately predict the number of roll-offs, although the waveform of the applied power is clearly not realistic. If current voltages are employed, the applied power waveform matches well with those reported experimentally, but there are significantly fewer roll-offs. Our computer results were overall into the ranges of experimental ones. CONCLUSIONS The proposed models reproduce reasonably well the electrical-thermal performance and coagulation zone size obtained during an impedance-controlled pulsing protocol.
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Affiliation(s)
- Macarena Trujillo
- a Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València , Spain
| | - Jose Bon
- b Food Technology Department , Universitat Politècnica de València , Spain
| | - María José Rivera
- c Applied Mathematics Department , Universitat Politècnica de València , Spain
| | - Fernando Burdío
- d Department of Surgery , Hospital del Mar , Barcelona , Spain
| | - Enrique Berjano
- e Biomedical Synergy, Department of Electronic Engineering , Universitat Politècnica de València , Spain
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Subramanian S, Schmidt DT, Rao MB, Mast TD. Dependence of ultrasound echo decorrelation on local tissue temperature during ex vivo radiofrequency ablation. Phys Med Biol 2016; 61:2356-71. [PMID: 26943026 DOI: 10.1088/0031-9155/61/6/2356] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
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).
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Affiliation(s)
- Swetha Subramanian
- Department of Biomedical, Chemical, and Environmental Engineering, University of Cincinnati, Cincinnati, OH, USA
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Yan S, Wu X, Wang W. 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. Int J Hyperthermia 2016; 32:231-8. [DOI: 10.3109/02656736.2016.1145746] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Abstract
Lung metastasectomy can prolong survival in patients with metastatic colorectal carcinoma. Thermal ablation offers a potential solution with similar reported survival outcomes. It has minimal effect on pulmonary function, or quality of life, can be repeated, and may be considered more acceptable to patients because of the associated shorter hospital stay and recovery. This review describes the indications, technique, reported outcomes, complications and radiologic appearances after thermal ablation of colorectal lung metastases.
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Affiliation(s)
- Carole A Ridge
- 1 Department of Radiology, Mater Misericordiae University Hospital, Dublin 7, Ireland ; 2 Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Stephen B Solomon
- 1 Department of Radiology, Mater Misericordiae University Hospital, Dublin 7, Ireland ; 2 Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
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Abstract
Although a surgical procedure is performed by visual inspection with histopathological assessment of the excised tumor and margins, percutaneous and noninvasive thermal ablation is performed strictly with the aid of imaging. Applicator guidance into the target zone, treatment monitoring and verification, and clinical follow-up rely on effective imaging. Detailed discussion of imaging is beyond the scope of this article, but the influence of imaging on the choice of thermal ablation or procedural approach will be discussed as needed. More information on imaging for interventional therapies can be found in other articles in this issue of IEEE Pulse.
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Zhang B, Moser MAJ, Zhang EM, Luo Y, Zhang W. Numerical analysis of the relationship between the area of target tissue necrosis and the size of target tissue in liver tumours with pulsed radiofrequency ablation. Int J Hyperthermia 2015; 31:715-25. [PMID: 26360111 DOI: 10.3109/02656736.2015.1058429] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Radiofrequency ablation (RFA) is currently restricted to the treatment of target tissues with a small size (<3 cm in diameter). To overcome this problem with RFA, some phenomena need to be understood first. The study presented in this paper investigated the relationship between the area of target tissue necrosis (TTN) and the size of target tissue in pulsed radiofrequency ablation (PRFA). MATERIALS AND METHODS Liver tumour, one of the common targets of RFA in clinical practice, was used as the target tissue in this study. Two types of pulsed RF power supply methods (half-square and half-sine) and three target tissues with different sizes (25 mm, 30 mm and 35 mm in diameter) were studied using finite element modelling. The finite element model (FEM) was validated by using an in vitro experiment with porcine liver tissue. The first roll-off occurrence or 720 s, whichever occurs first, was chosen as the ablation termination criterion in this study. RESULTS For each target tissue size, the largest TTN area was obtained using the maximum voltage applied (MVA) without roll-off occurrence. In this study, target tissues with a 25 mm diameter can be ablated cleanly but target tissues with 30-mm and 35-mm failed to be ablated. CONCLUSIONS The half-square PRFA could achieve a larger TTN area than the half-sine PRFA. The MVA decreases with an increase in the target tissue diameter in both the half-square PRFA and the half-sine PRFA. The findings of this study are in agreement with the clinical results that lesions (≥ 3 cm in diameter) have less favourable results from RFA.
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Affiliation(s)
- Bing Zhang
- a Division of Biomedical Engineering , University of Saskatchewan , Saskatoon , Canada
| | - Michael A J Moser
- b Department of Surgery , University of Saskatchewan , Saskatoon , Canada
| | - Edwin M Zhang
- c Department of Radiology and Diagnostic Imaging , University of Alberta , Edmonton , Canada
| | - Yigang Luo
- b Department of Surgery , University of Saskatchewan , Saskatoon , Canada
| | - Wenjun Zhang
- a Division of Biomedical Engineering , University of Saskatchewan , Saskatoon , Canada .,d Complex and Intelligent Systems Centre, School of Mechanical and Power Engineering, East China University of Science and Technology , Shanghai , China , and.,e Department of Mechanical Engineering , University of Saskatchewan , Saskatoon , Saskatchewan , Canada
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Zhang B, Moser MAJ, Zhang EM, Luo Y, Zhang H, Zhang W. Study of the relationship between the target tissue necrosis volume and the target tissue size in liver tumours using two-compartment finite element RFA modelling. Int J Hyperthermia 2015; 30:593-602. [PMID: 25430990 DOI: 10.3109/02656736.2014.984000] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The aim of this study was to investigate the relationship between the target tissue necrosis volume and the target tissue size during the radiofrequency ablation (RFA) procedure. MATERIALS AND METHODS The target tissues with four different sizes (dxy = 20, 25, 30 and 35 mm) were modelled using a two-compartment radiofrequency ablation model. Different voltages were applied to seek the maximum target tissue necrosis volume for each target tissue size. The first roll-off occurrence or the standard ablation time (12 min) was taken as the sign for the termination of the RFA procedure. RESULTS Four different maximum voltages without the roll-off occurrence were found for the four different sizes of target tissues (dxy = 20, 25, 30 and 35 mm), and they were 36.6, 35.4, 33.9 and 32.5 V, respectively. The target tissues with diameters of 20, 25 mm can be cleanly ablated at their own maximum voltages applied (MVA) but the same finding was not found for the 35-mm target tissue. For the target tissue with diameter of 30 mm, the 50 °C isothermal contour (IT50) result showed that the target tissue can be cleanly ablated, but the same result did not show in the Arrhenius damage model result. Furthermore, two optimal RFA protocols with a minimal thermal damage to the healthy tissues were found for the target tissues with diameters of 20 and 25 mm, respectively. CONCLUSIONS The study suggests that target tissues of different sizes should be treated with different RFA protocols. The maximum target tissue volume was achieved with the MVA without the roll-off occurrence for each target tissue size when a constant RF power supply was used.
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Affiliation(s)
- Bing Zhang
- Complex and Intelligent Systems Centre, School of Mechanical and Power Engineering, East China University Science and Technology , Shanghai , China
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Pillai K, Al-Alem I, Akhter J, Chua TC, Shehata M, Morris DL. Effect of Nonparallel Placement of In-Circle Bipolar Radiofrequency Ablation Probes on Volume of Tissue Ablated With Heat Sink. Surg Innov 2015; 22:223-234. [DOI: 10.1177/1553350614539047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Objectives. Percutaneous bipolar radiofrequency ablation (RFA) is a minimally invasive technique for treating liver tumors. It is not always possible to insert the bipolar probes parallel to each other on either side of tumor, since it restricts maneuverability away from vital structures or ablate certain tumor shape. Therefore, we investigated how nonparallel placement of probes affected ablation. Methods. Bipolar RFA in parallel and in divergent positions were submerged in tissue model (800 mL egg white) at 37°C and ablated. Temperature probes, T1 and T2 were placed 8.00 mm below the tip of the probes, T3 in between the probe coil elements and T4 and T5 at water inlet and outlet, respectively. Both models with heat sink (+HS) and without (−HS) were investigated. Results. The mean ablated tissue volume, mass, density and height increased linearly with unit angle increase for −HS model. With +HS, a smaller increase in mean volume and mass, a slightly greater increase in mean density but a reduction in height of tissue was seen. The mean ablation time and duration of maximum temperature with +HS was slightly larger, compared with −HS, while −HS ablated at a slightly higher temperature. The heat sink present was minimal for probes in parallel position compared to nonparallel positions. Conclusion. Divergence from parallel insertion of bipolar RFA probes increased the mean volume, mass, and density of tissue ablated. However, the presence of large heat sinks may limit the application of this technique, when tumors border on larger vessels.
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Affiliation(s)
- Krishna Pillai
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
| | - Ihssan Al-Alem
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
| | - Javed Akhter
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
| | - Terence C. Chua
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
| | - Mena Shehata
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
| | - David L. Morris
- University of New South Wales, St. George Hospital, Kogarah, New South Wales, Australia
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Fukushima T, Ikeda K, Kawamura Y, Sorin Y, Hosaka T, Kobayashi M, Saitoh S, Sezaki H, Akuta N, Suzuki F, Suzuki Y, Arase Y, Kumada H. Randomized Controlled Trial Comparing the Efficacy of Impedance Control and Temperature Control of Radiofrequency Interstitial Thermal Ablation for Treating Small Hepatocellular Carcinoma. Oncology 2015; 89:47-52. [DOI: 10.1159/000375166] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 01/09/2015] [Indexed: 11/19/2022]
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Wallace N, Dicker S, Lewin P, Wrenn SP. Influence of nesting shell size on brightness longevity and resistance to ultrasound-induced dissolution during enhanced B-mode contrast imaging. ULTRASONICS 2014; 54:2099-2108. [PMID: 25041980 DOI: 10.1016/j.ultras.2014.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 06/18/2014] [Accepted: 06/20/2014] [Indexed: 06/03/2023]
Abstract
This study aims to bridge the gap between transport mechanisms of an improved ultrasound contrast agent (UCA) and its resulting behavior in a clinical imaging study. Phospholipid-shelled microbubbles nested within the aqueous core of a polymer microcapsule are examined for their use and feasibility as an improved UCA. The nested formulation provides contrast comparable to traditional formulations, specifically an SF6 microbubble coated by a DSPC PEG-3000 monolayer, with the advantage that contrast persists at least nine times longer in a mock clinical, in vitro setting. The effectiveness of the sample was measured using a contrast ratio in units of decibels (dB) which compares the brightness of the nested microbubbles to a reference value of a phantom tissue mimic. During a 40min imaging study, six nesting formulations with average outer capsule diameters of 1.95, 2.53, 5.55, 9.95, 14.95, and 20.51μm reached final contrast ratio values of 0.25, 2.35, 3.68, 4.51, 5.93, and 8.00dB, respectively. The starting contrast ratio in each case was approximately 8dB and accounts for the brightness attributed to the nesting shell. As compared with empty microcapsules (no microbubbles nested within), enhancement of the initial contrast ratio increased systematically with decreasing microcapsule size. The time required to reach a steady state in the temporal contrast ratio profile also varied with microcapsule diameter and was found to be 420s for each of the four smallest shell diameters and 210s and 150s, respectively, for the largest two shell diameters. All nested formulations were longer-lived and gave higher final contrast ratios than a control sample comprising un-nested, but otherwise equivalent, microbubbles. Specifically, the contrast ratio of the un-nested microbubbles decreased to a negative value after 4min of continuous ultrasound exposure with complete disappearance of the microbubbles after 15min whereas all nested formulations maintained positive contrast ratio values for the duration of the 40min trial. The results are consistent with two distinct stages of gas transport: in the first stage, passive diffusion occurs under ambient conditions across the microbubble monolayer within the first few minutes after formulation until the aqueous interior of the microcapsule is saturated with gas; in the second stage ultrasound drives additional gas dissolution even further due to pressure modulation. It is important to understand the chemistry and transport mechanisms of this contrast agent under the influence of ultrasound to attain better perspicacity for enhanced applications in imaging. Results from this study will facilitate future preclinical studies and clinical applications of nested microbubbles for therapeutic and diagnostic imaging.
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Affiliation(s)
- N Wallace
- Department of Chemical Engineering, Drexel University, Philadelphia, PA, USA
| | - S Dicker
- Department of Chemical Engineering, Drexel University, Philadelphia, PA, USA
| | - P Lewin
- Department of Chemical Engineering, Drexel University, Philadelphia, PA, USA
| | - S P Wrenn
- Department of Chemical Engineering, Drexel University, Philadelphia, PA, USA.
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Ahmed M, Solbiati L, Brace CL, Breen DJ, Callstrom MR, Charboneau JW, Chen MH, Choi BI, de Baère T, Dodd GD, Dupuy DE, Gervais DA, Gianfelice D, Gillams AR, Lee FT, Leen E, Lencioni R, Littrup PJ, Livraghi T, Lu DS, McGahan JP, Meloni MF, Nikolic B, Pereira PL, Liang P, Rhim H, Rose SC, Salem R, Sofocleous CT, Solomon SB, Soulen MC, Tanaka M, Vogl TJ, Wood BJ, Goldberg SN. Image-guided tumor ablation: standardization of terminology and reporting criteria--a 10-year update. J Vasc Interv Radiol 2014; 25:1691-705.e4. [PMID: 25442132 PMCID: PMC7660986 DOI: 10.1016/j.jvir.2014.08.027] [Citation(s) in RCA: 332] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 02/11/2014] [Accepted: 03/26/2014] [Indexed: 12/12/2022] Open
Abstract
Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes.
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Affiliation(s)
- Muneeb Ahmed
- Department of Radiology, Beth Israel Deaconess Medical Center 1 Deaconess Rd, WCC-308B, Boston, MA 02215.
| | - Luigi Solbiati
- Department of Radiology, Ospedale Generale, Busto Arsizio, Italy
| | - Christopher L Brace
- Departments of Radiology, Biomedical Engineering, and Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - David J Breen
- Department of Radiology, Southampton University Hospitals, Southampton, England
| | | | | | - Min-Hua Chen
- Department of Ultrasound, School of Oncology, Peking University, Beijing, China
| | - Byung Ihn Choi
- Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea
| | - Thierry de Baère
- Department of Imaging, Institut de Cancérologie Gustave Roussy, Villejuif, France
| | - Gerald D Dodd
- Department of Radiology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Damian E Dupuy
- Department of Diagnostic Radiology, Rhode Island Hospital, Providence, Rhode Island
| | - Debra A Gervais
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - David Gianfelice
- Medical Imaging, University Health Network, Laval, Quebec, Canada
| | | | - Fred T Lee
- Department of Radiology, University of Wisconsin Hospital and Clinics, Madison, Wisconsin
| | - Edward Leen
- Department of Radiology, Royal Infirmary, Glasgow, Scotland
| | - Riccardo Lencioni
- Department of Diagnostic Imaging and Intervention, Cisanello Hospital, Pisa University Hospital and School of Medicine, University of Pisa, Pisa, Italy
| | - Peter J Littrup
- Department of Radiology, Karmonos Cancer Institute, Wayne State University, Detroit, Michigan
| | | | - David S Lu
- Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - John P McGahan
- Department of Radiology, Ambulatory Care Center, UC Davis Medical Center, Sacramento, California
| | | | - Boris Nikolic
- Department of Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania
| | - Philippe L Pereira
- Clinic of Radiology, Minimally-Invasive Therapies and Nuclear Medicine, Academic Hospital Ruprecht-Karls-University Heidelberg, Heilbronn, Germany
| | - Ping Liang
- Department of Interventional Ultrasound, Chinese PLA General Hospital, Beijing, China
| | - Hyunchul Rhim
- Department of Diagnostic Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Steven C Rose
- Department of Radiology, University of California, San Diego, San Diego, California
| | - Riad Salem
- Department of Radiology, Northwestern University, Chicago, Illinois
| | | | - Stephen B Solomon
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Michael C Soulen
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Thomas J Vogl
- Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Johann Wolfgang Goethe-University, Frankfurt, Germany
| | - Bradford J Wood
- Radiology and Imaging Science, National Institutes of Health, Bethesda, Maryland
| | - S Nahum Goldberg
- Department of Radiology, Image-Guided Therapy and Interventional Oncology Unit, Hadassah Hebrew University Medical Center, Jerusalem, Israel
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Jaque D, Martínez Maestro L, del Rosal B, Haro-Gonzalez P, Benayas A, Plaza JL, Martín Rodríguez E, García Solé J. Nanoparticles for photothermal therapies. NANOSCALE 2014; 6:9494-530. [PMID: 25030381 DOI: 10.1039/c4nr00708e] [Citation(s) in RCA: 1045] [Impact Index Per Article: 104.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The current status of the use of nanoparticles for photothermal treatments is reviewed in detail. The different families of heating nanoparticles are described paying special attention to the physical mechanisms at the root of the light-to-heat conversion processes. The heating efficiencies and spectral working ranges are listed and compared. The most important results obtained in both in vivo and in vitro nanoparticle assisted photothermal treatments are summarized. The advantages and disadvantages of the different heating nanoparticles are discussed.
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Affiliation(s)
- D Jaque
- Fluorescence Imaging Group, Departamento de Física de Materiales e Instituto Nicolás Cabrera, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Cantoblanco, Madrid 28049, Spain.
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Yoon YI, Kim KS, Kwon YS, Cho HS, Lee HJ, Yoon CJ, Yoon TJ. Synthesis of Gold Nanoparticles by Electro-reduction Method and Their Application as an Electro-hyperthermia System. B KOREAN CHEM SOC 2014. [DOI: 10.5012/bkcs.2014.35.6.1806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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A comparison of internally water-perfused and cryogenically cooled monopolar and bipolar radiofrequency applicators in ex vivo liver samples. Acad Radiol 2014; 21:661-6. [PMID: 24703480 DOI: 10.1016/j.acra.2014.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 02/04/2014] [Accepted: 02/04/2014] [Indexed: 12/19/2022]
Abstract
RATIONALE AND OBJECTIVES To evaluate the ex vivo ablation zones created in hepatic tissue using monopolar and bipolar gas- and water-cooled radiofrequency (RF) applicators. MATERIALS AND METHODS RF ablations were performed on ex vivo bovine liver tissue using closed circuit water-cooled and closed circuit cryogenically cooled (via CO₂ enthalpy) 15-ga linear-needle applicators. Both monopolar and bipolar electrode applicators were used, with the electric current administered ranging in 50-mA increments from 1100 to 1300 mA for the monopolar case, and from 500 to 700 mA for the bipolar case. Total ablation time was 15 minutes. Six tissue samples were ablated per setting. The ablated volumes were assumed to have a three-dimensional ellipsoid shape, with one long major axis and two smaller minor axes. Gross histology was used to measure the dimensions of the ablated regions to quantify the ablated volume, the dimensions of the axis, and the ratio between the long axis and the smallest minor axis, which was termed the ellipticity index. RESULTS The gas-cooled monopolar applicator achieved the largest short-axis ablation diameter (4.05 ± 0.4 cm), followed by the water-cooled monopolar applicator (3.18 ± 0.29 cm). With the bipolar applicator, the gas-cooled applicators also achieved larger short-axis ablation diameters (3.02 ± 0.15 cm) than the water-cooled applicators (2.72 ± 0.29 cm). The gas-cooled monopolar applicator also provided the largest ablation volume (42.7 ± 10.7 mL) and the most spherically shaped lesions (ellipticity index: 1.21 ± 0.10). Lesion size increased with injected current up to a threshold current of 1200/1250 mA (monopolar water-/gas-cooled) and 600/650 mA (bipolar water-/gas-cooled), but dropped at greater values. CONCLUSIONS Gas-cooled monopolar applicators were superior to the other tested applicators in terms of both volume and sphericity of the ablation zone.
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