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Wang Z, Liang M, Sun J, Zhang J, Li Y, Xu L, Han Y. Epicardial pulsed-field ablation-impact of electric field and heat distribution induced by coronary metallic stents. Front Cardiovasc Med 2024; 11:1445424. [PMID: 39267803 PMCID: PMC11391106 DOI: 10.3389/fcvm.2024.1445424] [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: 06/07/2024] [Accepted: 08/13/2024] [Indexed: 09/15/2024] Open
Abstract
Background Pulsed-field ablation (PFA) technique is a nonthermal ablation technique. No study has yet evaluated the effect of the positional relationship between the ablation electrode (AE) and the coronary metal stent (CMS) on the electric field distribution and temperature distribution in epicardial ablation. Our study aimed to evaluate the effect of the CMS on the electric field as well as the temperature distribution in different models. Methods Multi-angle modeling of the CMS and AE was performed. The PFA ablation region was evaluated with a field strength contour of 1,000 V/cm, which was used to assess the validity of the two-dimensional (2D) model simulation data as well as the distribution of the multi-angle electric field and temperature in the three-dimensional (3D) model. Results The presence of the CMS had little effect on the width of the ablation area (0.2 mm). In the 3D model, the temperature of the ablation area was highest when the angle between the AE and the CMS was in the 90° position (43.4°C, 41.3°C); a change in the distance between the AE and the CMS affected the temperature of the ablation area (maximum 2.1°C) and the width of the ablation (maximum 0.32 mm). Conclusion The presence of the CMS distorts the distribution of the electric field, but does not produce a change in the extent of the ablation damage, nor does it bring thermal damage to the ablation region. Different simulation models give similar results in PFA calculations, and this study effectively reduces the complexity of modeling simulation.
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Affiliation(s)
- Zhen Wang
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang, China
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
| | - Ming Liang
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
- National Key Laboratory of Frigid Zone Cardiovascular Diseases, General Hospital of Northern Theater Command, Shenyang, China
| | - Jingyang Sun
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
| | - Jie Zhang
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
| | - Yunhao Li
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
- Graduate School of China Medical University, China Medical University, Shenyang, China
| | - Lisheng Xu
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang, China
| | - Yaling Han
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
- National Key Laboratory of Frigid Zone Cardiovascular Diseases, General Hospital of Northern Theater Command, Shenyang, China
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Fang Z, Wu C, Cao L, Wang T, Hong X, Moser MAJ, Zhang W, Zhang B. Development of non-invasive flexible directional microwave ablation for central lung cancer: a simulation study. Phys Med Biol 2024; 69:09NT04. [PMID: 38527368 DOI: 10.1088/1361-6560/ad3795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 03/25/2024] [Indexed: 03/27/2024]
Abstract
Transbronchial microwave ablation (MWA) with flexible antennas has gradually become an attractive alternative to percutaneous MWA for lung cancer due to its characteristic of non-invasiveness. However, flexible antennas for the precision ablation of lung tumors that are adjacent to critical bronchial structures are still not available. In this study, a non-invasive flexible directional (FD) antenna for early stage central lung tumors surrounding the bronchia was proposed. A comprehensive numerical MWA model with the FD antenna was developed in a real human-sized left lung model. The structure of the antenna and the treatment protocol were optimized by a generic algorithm for the precision ablation of two cases of early stage central lung cancer (i.e. spherical-like and ellipsoidal tumors). The electromagnetic efficiency of the optimized antenna was also improved by implementing an optimizedπ-matching network for impedance matching. The results indicate that the electromagnetic energy of MWA can be restricted to a particular area for precision ablation of specific lung tumors using the FD antenna. This study contributes to the field of lung cancer management with MWA.
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Affiliation(s)
- Zheng Fang
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, People's Republic of China
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Canada
| | - Chen Wu
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, People's Republic of China
| | - Lin Cao
- Department of Automatic Control and Systems Engineering, the University of Sheffield, Sheffield, United Kingdom
| | - Tao Wang
- Department of Interventional Oncology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Xiaowu Hong
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai, People's Republic of China
- Research Institute of Fudan University, Ningbo, People's Republic of China
| | - Michael A J Moser
- Department of Surgery, University of Saskatchewan, Saskatoon, Canada
| | - Wenjun Zhang
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Canada
| | - Bing Zhang
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, People's Republic of China
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Wu C, Huang H, Liu Y, Chen L, Yu S, Moser MAJ, Zhang W, Fang Z, Zhang B. Optimal design of aperiodic tri-slot antennas for the conformal ablation of liver tumors using an experimentally validated MWA computer model. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 242:107799. [PMID: 37703699 DOI: 10.1016/j.cmpb.2023.107799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 09/03/2023] [Accepted: 09/03/2023] [Indexed: 09/15/2023]
Abstract
OBJECTIVE This study aims to demonstrate that the conformal microwave ablation (MWA) of liver tumors could be attained by optimizing the structure of an aperiodic tri-slot coaxial antenna, its insertion depth, and input power. METHODS A computational MWA model with an aperiodic tri-slot coaxial antenna operating at the frequency of 2.45 GHz was built and validated by both an ex vivo and a pilot in vivo experiment with porcine healthy livers. The validated in vivo computational MWA model implemented with a liver tumor was then used as a testbed to investigate the conformal ablation of liver tumors. Five liver tumors in different sizes and shapes were investigated. A genetic algorithm optimization method (NSGA-II) was used to optimize the structure of antenna, insertion depth of antenna, and microwave antenna input power for the conformal ablation of liver tumors. RESULTS The validation results showed that a good agreement in both the spatiotemporal temperature distribution and ablation zone was found between the computer model and the ex vivo experiments at both 45 W, 5 min and 60 W, 3 min treatments and the in vivo experiment at 45 W, 5 min treatment. The optimized simulation results confirmed that five cases of liver tumors in different sizes and shapes can be conformally ablated by optimizing the aperiodic tri-slot coaxial antenna, antenna insertion depth, and microwave antenna input power. CONCLUSION This paper demonstrates that the aperiodic tri-slot coaxial antenna can be optimized with the insertion depth and input power for the conformal ablation of liver tumors, regardless the size and shape of liver tumors.
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Affiliation(s)
- Chen Wu
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China
| | - Hangming Huang
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China
| | - Yongfang Liu
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201412, China
| | - Lingchao Chen
- Department of Neurosurgery, Huashan Hospital Shanghai Medical College, Fudan University, Shanghai 200040, China
| | - Shuangquan Yu
- Department of Neurosurgery, Huashan Hospital Shanghai Medical College, Fudan University, Shanghai 200040, China
| | - Michael A J Moser
- Department of Surgery, University of Saskatchewan, Saskatoon, Canada
| | - Wenjun Zhang
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Canada
| | - Zheng Fang
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, Canada.
| | - Bing Zhang
- Intelligent Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China.
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Farahinia A, Zhang W, Badea I. Recent Developments in Inertial and Centrifugal Microfluidic Systems along with the Involved Forces for Cancer Cell Separation: A Review. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23115300. [PMID: 37300027 DOI: 10.3390/s23115300] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/23/2023] [Accepted: 05/17/2023] [Indexed: 06/12/2023]
Abstract
The treatment of cancers is a significant challenge in the healthcare context today. Spreading circulating tumor cells (CTCs) throughout the body will eventually lead to cancer metastasis and produce new tumors near the healthy tissues. Therefore, separating these invading cells and extracting cues from them is extremely important for determining the rate of cancer progression inside the body and for the development of individualized treatments, especially at the beginning of the metastasis process. The continuous and fast separation of CTCs has recently been achieved using numerous separation techniques, some of which involve multiple high-level operational protocols. Although a simple blood test can detect the presence of CTCs in the blood circulation system, the detection is still restricted due to the scarcity and heterogeneity of CTCs. The development of more reliable and effective techniques is thus highly desired. The technology of microfluidic devices is promising among many other bio-chemical and bio-physical technologies. This paper reviews recent developments in the two types of microfluidic devices, which are based on the size and/or density of cells, for separating cancer cells. The goal of this review is to identify knowledge or technology gaps and to suggest future works.
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Affiliation(s)
- Alireza Farahinia
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
| | - Wenjun Zhang
- Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
| | - Ildiko Badea
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
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McInnes AD, Moser MAJ, Chen X. Preparation and Use of Decellularized Extracellular Matrix for Tissue Engineering. J Funct Biomater 2022; 13:jfb13040240. [PMID: 36412881 PMCID: PMC9680265 DOI: 10.3390/jfb13040240] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/22/2022] [Accepted: 11/05/2022] [Indexed: 11/16/2022] Open
Abstract
The multidisciplinary fields of tissue engineering and regenerative medicine have the potential to revolutionize the practise of medicine through the abilities to repair, regenerate, or replace tissues and organs with functional engineered constructs. To this end, tissue engineering combines scaffolding materials with cells and biologically active molecules into constructs with the appropriate structures and properties for tissue/organ regeneration, where scaffolding materials and biomolecules are the keys to mimic the native extracellular matrix (ECM). For this, one emerging way is to decellularize the native ECM into the materials suitable for, directly or in combination with other materials, creating functional constructs. Over the past decade, decellularized ECM (or dECM) has greatly facilitated the advance of tissue engineering and regenerative medicine, while being challenged in many ways. This article reviews the recent development of dECM for tissue engineering and regenerative medicine, with a focus on the preparation of dECM along with its influence on cell culture, the modification of dECM for use as a scaffolding material, and the novel techniques and emerging trends in processing dECM into functional constructs. We highlight the success of dECM and constructs in the in vitro, in vivo, and clinical applications and further identify the key issues and challenges involved, along with a discussion of future research directions.
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Affiliation(s)
- Adam D. McInnes
- Division of Biomedical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
- Correspondence: ; Tel.: +1-306-966-5435
| | - Michael A. J. Moser
- Department of Surgery, Health Sciences Building, University of Saskatchewan, Saskatoon, SK S7N 0W8, Canada
| | - Xiongbiao Chen
- Division of Biomedical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
- Department of Mechanical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
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Iredale E, Voigt B, Rankin A, Kim KW, Chen JZ, Schmid S, Hebb MO, Peters TM, Wong E. Planning System for the Optimization of Electric Field Delivery using Implanted Electrodes for Brain Tumor Control. Med Phys 2022; 49:6055-6067. [PMID: 35754362 DOI: 10.1002/mp.15825] [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: 02/03/2022] [Revised: 06/06/2022] [Accepted: 06/17/2022] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND The use of non-ionizing electric fields from low intensity voltage sources (<10 V) to control malignant tumor growth is showing increasing potential as a cancer treatment modality. A method of applying these low intensity electric fields using multiple implanted electrodes within or adjacent to tumor volumes has been termed as intratumoral modulation therapy (IMT). PURPOSE This study explores advancements in the previously established IMT optimization algorithm, and the development of a custom treatment planning system for patient specific IMT. The practicality of the treatment planning system is demonstrated by implementing the full optimization pipeline on a brain phantom with robotic electrode implantation, post-operative imaging, and treatment stimulation. METHODS The integrated planning pipeline in 3D Slicer begins with importing and segmenting patient magnetic resonance images (MRI) or computed tomography (CT) images. The segmentation process is manual, followed by a semi-automatic smoothing step that allows the segmented brain and tumor mesh volumes to be smoothed and simplified by applying selected filters. Electrode trajectories are planned manually on the patient MRI or CT by selecting insertion and tip coordinates for a chosen number of electrodes. The electrode tip positions, and stimulation parameters (phase shift and voltage) can then be optimized with the custom semi-automatic IMT optimization algorithm where users can select the prescription electric field, voltage amplitude limit, tissue electrical properties, nearby organs at risk, optimization parameters (electrode tip location, individual contact phase shift and voltage), desired field coverage percent, and field conformity optimization. Tables of optimization results are displayed, and the resulting electric field is visualized as a field-map superimposed on the MR or CT image, with 3D renderings of the brain, tumor, and electrodes. Optimized electrode coordinates are transferred to robotic electrode implantation software to enable planning and subsequent implantation of the electrodes at the desired trajectories. RESULTS An IMT treatment planning system was developed that incorporates patient specific MRI or CT, segmentation, volume smoothing, electrode trajectory planning, electrode tip location and stimulation parameter optimization, and results visualization. All previous manual pipeline steps operating on diverse software platforms were coalesced into a single semi-automated 3D Slicer based user interface. Brain phantom validation of the full system implementation was successful in pre-operative planning, robotic electrode implantation, and post-operative treatment planning to adjust stimulation parameters based on actual implant locations. Voltage measurements were obtained in the brain phantom to determine the electrical parameters of the phantom and validate the simulated electric field distribution. CONCLUSIONS A custom treatment planning and implantation system for IMT has been developed in this study, and validated on a phantom brain model, providing an essential step in advancing IMT technology towards future clinical safety and efficacy investigations. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Erin Iredale
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Brynn Voigt
- Department of Physics and Astronomy, Western University, London, ON, Canada
| | - Adam Rankin
- Robarts Research Institute, Western University, London, ON, Canada
| | - Kyungho W Kim
- Department of Physics and Astronomy, Western University, London, ON, Canada
| | - Jeff Z Chen
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Susanne Schmid
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Matthew O Hebb
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.,Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Terry M Peters
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.,Robarts Research Institute, Western University, London, ON, Canada
| | - Eugene Wong
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.,Department of Physics and Astronomy, Western University, London, ON, Canada
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Perera-Bel E, Mercadal B, Garcia-Sanchez T, Gonzalez Ballester MA, Ivorra A. Modeling methods for treatment planning in overlapping electroporation treatments. IEEE Trans Biomed Eng 2021; 69:1318-1327. [PMID: 34559631 DOI: 10.1109/tbme.2021.3115029] [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: 11/06/2022]
Abstract
OBJECTIVE Irreversible electroporation (IRE) is a non thermal tissue ablation therapy which is induced by applying high voltage waveforms across electrode pairs. When multiple electrode pairs are sequentially used, the treatment volume (TV) is typically computed as the geometric union of the TVs of individual pairs. However, this method neglects that some regions are exposed to overlapping treatments. Recently, a model describing cell survival probability was introduced which effectively predicted TV with overlapping fields in vivo. However, treatment overlap has yet to be quantified. This study characterizes TV overlap in a controlled in vitro setup with the two existing methods which are compared to an adapted logistic model proposed here. METHODS CHO cells were immobilized in agarose gel. Initially, we characterized the electric field threshold and the cell survival probability for overlapping treatments. Subsequently, we created a 2D setup where we compared and validated the accuracy of the different methods in predicting the TV. RESULTS Overlap can reduce the electric field threshold required to induce cell death, particularly for treatments with low pulse number. However, it does not have a major impact on TV in the models assayed here, and all the studied methods predict TV with similar accuracy. CONCLUSION Treatment overlap has a minor influence in the TV for typical protocols found in IRE therapies. SIGNIFICANCE This study provides evidence that the modeling method used in most pre-clinical and clinical studies seems adequate.
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Wardhana G, Almeida JP, Abayazid M, Fütterer JJ. Development of a thermal model for irreversible electroporation: an approach to estimate and optimize the IRE protocols. Int J Comput Assist Radiol Surg 2021; 16:1325-1334. [PMID: 34032965 PMCID: PMC8295143 DOI: 10.1007/s11548-021-02403-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 05/07/2021] [Indexed: 11/27/2022]
Abstract
Purpose Irreversible electroporation (IRE) is an emerging technique that has drawn attention in the field of cancer treatment. IRE uses non-thermal electric pulses to induce death of cancerous cells. However, recent studies have shown that the application of this technique may result in heating of the tissue. There is still room for improving its efficiency and defining better treatment protocols. This study investigates the optimal IRE protocols that avoiding the thermal damage during the IRE treatment. Methods Electrode and pulse parameter are investigated. Finite element models are created to evaluate the ablation area and the temperature changes in the tissue. The model is validated experimentally in bovine liver tissue, while the parameters were optimized using response surface method (RSM). Results From analysis of variance, the parameter of electrode distance and input voltage has significant effect to the temperature rise in the IRE treatment of bovine liver (P = 0.020 and P = 0.003 respectively). Meanwhile, only the input voltage significantly affects the ablation area (P < 0.001). The optimal result from RSM showed that for maximum ablation area 250.82mm2 with no thermal damage, the IRE protocol consisted of an active electrode length of 10 mm, a distance between electrodes of 10 mm, and the delivery of 50 pulses of 41.21 µs and 3000 V. Conclusions The approach presented in this study allows the optimization of the IRE protocols. An optimal IRE protocol that maximizes the ablation area was successfully calculated which can be applied with no risk of thermal damage to the tissue.
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Affiliation(s)
- Girindra Wardhana
- Department of Robotics and Mechatronics, The Faculty of Electrical Engineering, Mathematics and Computer Science, Technical Medical Centre, University of Twente, 7522 NB, Enschede, The Netherlands.
| | - João Pedro Almeida
- Department of Robotics and Mechatronics, The Faculty of Electrical Engineering, Mathematics and Computer Science, Technical Medical Centre, University of Twente, 7522 NB, Enschede, The Netherlands
| | - Momen Abayazid
- Department of Robotics and Mechatronics, The Faculty of Electrical Engineering, Mathematics and Computer Science, Technical Medical Centre, University of Twente, 7522 NB, Enschede, The Netherlands
| | - Jurgen J Fütterer
- Department of Robotics and Mechatronics, The Faculty of Electrical Engineering, Mathematics and Computer Science, Technical Medical Centre, University of Twente, 7522 NB, Enschede, The Netherlands
- Department of Medical Imaging, Radboud University Medical Center Nijmegen, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, The Netherlands
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Irreversible Electroporation Enhanced by Radiofrequency Ablation: An In Vitro and Computational Study in a 3D Liver Tumor Model. Ann Biomed Eng 2021; 49:2126-2138. [PMID: 33594637 DOI: 10.1007/s10439-021-02734-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 01/15/2021] [Indexed: 12/24/2022]
Abstract
In the present study, we used a computational and experimental study in a 3D liver tumor model (LTM) to explore the tumor ablation enhancement of irreversible electroporation (IRE) by pre-heating with radiofrequency ablation (RFA) and elucidate the mechanism whereby this enhancement occurs. Three ablation protocols, including IRE alone, RFA45 → IRE (with the pre-heating temperature of 45 °C), and RFA60 → IRE (with the pre-heating temperature of 60 °C) were investigated. Both the thermal conductivity and electrical conductivity of the 3D LTM were characterized with the change in the pre-heating temperature. The results showed, compared to IRE alone, a significant increase in the tumor ablation volume (19.59 [Formula: see text] 0.61 vs. 15.29 ± 0.61 mm3, p = 0.002 and 22.87 [Formula: see text] 0.35 vs. 15.29 ± 0.61 mm3, p < 0.001) was observed with both RFA45 → IRE and RFA60 → IRE, leading to a decrease in lethal electric filed strength (8 and 17%, correspondingly). The mechanism can be attributed to the change of cell microenvironment by pre-heating and/or a synergistic effect of RFA and IRE. The proposed enhancing method might contribute to the improvement of interventional oncology in the treatment of large tumors close to critical organs (e.g., large blood vessels and bile ducts).
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