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Chelales E, von Windheim K, Banipal AS, Siebeneck E, Benham C, Nief CA, Crouch B, Everitt JI, Sag AA, Katz DF, Ramanujam N. Determining the Relationship between Delivery Parameters and Ablation Distribution for Novel Gel Ethanol Percutaneous Therapy in Ex Vivo Swine Liver. Polymers (Basel) 2024; 16:997. [PMID: 38611255 PMCID: PMC11013462 DOI: 10.3390/polym16070997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/22/2024] [Accepted: 04/01/2024] [Indexed: 04/14/2024] Open
Abstract
Ethyl cellulose-ethanol (ECE) is emerging as a promising formulation for ablative injections, with more controllable injection distributions than those from traditional liquid ethanol. This study evaluates the influence of salient injection parameters on forces needed for infusion, depot volume, retention, and shape in a large animal model relevant to human applications. Experiments were conducted to investigate how infusion volume (0.5 mL to 2.5 mL), ECE concentration (6% or 12%), needle gauge (22 G or 27 G), and infusion rate (10 mL/h) impacted the force of infusion into air using a load cell. These parameters, with the addition of manual infusion, were investigated to elucidate their influence on depot volume, retention, and shape (aspect ratio), measured using CT imaging, in an ex vivo swine liver model. Force during injection increased significantly for 12% compared to 6% ECE and for 27 G needles compared to 22 G. Force variability increased with higher ECE concentration and smaller needle diameter. As infusion volume increased, 12% ECE achieved superior depot volume compared to 6% ECE. For all infusion volumes, 12% ECE achieved superior retention compared to 6% ECE. Needle gauge and infusion rate had little influence on the observed depot volume or retention; however, the smaller needles resulted in higher variability in depot shape for 12% ECE. These results help us understand the multivariate nature of injection performance, informing injection protocol designs for ablations using gel ethanol and infusion, with volumes relevant to human applications.
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Affiliation(s)
- Erika Chelales
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Katriana von Windheim
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Arshbir Singh Banipal
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Elizabeth Siebeneck
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Claire Benham
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Corrine A. Nief
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Brian Crouch
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Jeffrey I. Everitt
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA;
| | - Alan Alper Sag
- Department of Radiology, Division of Vascular and Interventional Radiology, Duke University Medical Center, Durham, NC 27710, USA
| | - David F. Katz
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
| | - Nirmala Ramanujam
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; (K.v.W.); (A.S.B.); (C.A.N.)
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Mathy RM, Giannakis A, Franke M, Winiger A, Kauczor HU, Chang DH. Factors Impacting Microwave Ablation Zone Sizes: A Retrospective Analysis. Cancers (Basel) 2024; 16:1279. [PMID: 38610957 PMCID: PMC11011160 DOI: 10.3390/cancers16071279] [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: 02/02/2024] [Revised: 03/01/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024] Open
Abstract
PURPOSE Evaluation of the influence of intrinsic and extrinsic conditions on ablation zone volumes (AZV) after microwave ablation (MWA). METHODS Retrospective analysis of 38 MWAs of therapy-naïve liver tumours performed with the NeuWave PR probe. Ablations were performed either in the 'standard mode' (65 W, 10 min) or in the 'surgical mode' (95 W, 1 min, then 65 W, 10 min). AZV measurements were obtained from contrast-enhanced computed tomography immediately post-ablation. RESULTS AZVs in the 'standard mode' were smaller than predicted by the manufacturer (length 3.6 ± 0.6 cm, 23% below 4.7 cm; width 2.7 ± 0.6, 23% below 3.5 cm). Ablation zone past the tip was limited to 6 mm in 28/32 ablations. Differences in AZV between the 'surgical mode' and 'standard mode' were not significant (15.6 ± 7.8 mL vs. 13.9 ± 8.8 mL, p = 0.6). AZVs were significantly larger in case of hepatocellular carcinomas (HCCs) (n = 19) compared to metastasis (n = 19; 17.8 ± 9.9 mL vs. 10.1 ± 5.1 mL, p = 0.01) and in non-perivascular tumour location (n = 14) compared to perivascular location (n = 24, 18.7 ± 10.4 mL vs. 11.7 ± 6.1 mL, p = 0.012), with both factors remaining significant in two-way analysis of variance (HCC vs. metastasis: p = 0.02; perivascular vs. non-perivascular tumour location: p = 0.044). CONCLUSION Larger AZVs can be expected in cases of HCCs compared with metastases and in non-perivascular locations. Using the 'surgical mode' does not increase AZV significantly.
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Affiliation(s)
- René Michael Mathy
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; (A.G.)
| | - Athanasios Giannakis
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; (A.G.)
- 2nd Department of Radiology, University General Hospital, “ATTIKON” Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - Mareike Franke
- Department of Radiology, Cantonal Hospital of Lucerne, 6000 Lucerne, Switzerland
| | - Alain Winiger
- Department of Radiology, Cantonal Hospital of Lucerne, 6000 Lucerne, Switzerland
| | - Hans-Ulrich Kauczor
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; (A.G.)
| | - De-Hua Chang
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; (A.G.)
- Department of Radiology, Cantonal Hospital of Lucerne, 6000 Lucerne, Switzerland
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Meyerholz DK, Burrough ER, Kirchhof N, Anderson DJ, Helke KL. Swine models in translational research and medicine. Vet Pathol 2024:3009858231222235. [PMID: 38197394 DOI: 10.1177/03009858231222235] [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: 01/11/2024]
Abstract
Swine are increasingly studied as animal models of human disease. The anatomy, size, longevity, physiology, immune system, and metabolism of swine are more like humans than traditional rodent models. In addition, the size of swine is preferred for surgical placement and testing of medical devices destined for humans. These features make swine useful for biomedical, pharmacological, and toxicological research. With recent advances in gene-editing technologies, genetic modifications can readily and efficiently be made in swine to study genetic disorders. In addition, gene-edited swine tissues are necessary for studies testing and validating xenotransplantation into humans to meet the critical shortfall of viable organs versus need. Underlying all of these biomedical applications, the knowledge of husbandry, background diseases and lesions, and biosecurity needs are important for productive, efficient, and reproducible research when using swine as a human disease model for basic research, preclinical testing, and translational studies.
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Hui TCH, How GY, Chim MSM, Pua U. Comparative Study of Ablation Zone of EMPRINT HP Microwave Device with Contemporary 2.4 GHz Microwave Devices in an Ex Vivo Porcine Liver Model. Diagnostics (Basel) 2023; 13:2702. [PMID: 37627962 PMCID: PMC10453042 DOI: 10.3390/diagnostics13162702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/14/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
(1) Background: Percutaneous microwave ablation (MWA) is an accepted treatment of non-operative liver cancer. This study compares the ablation zones of four commercially available 2.45 GHz MWA systems (Emprint, Eco, Neuwave, and Solero) in an ex vivo porcine liver model. (2) Methods: Ex vivo porcine livers (n = 85) were obtained. Two ablation time setting protocols were evaluated, the manufacturer's recommended maximum time and a 3 min time, performed at the manufacturer-recommended maximum power setting. A total of 236 ablation samples were created with 32 (13.6%) samples rejected. A total of 204 samples were included in the statistical analysis. (3) Results: For single-probe protocols, Emprint achieved ablation zones with the largest SAD. Significant differences were found in all comparisons for the 3 min time setting and for all comparisons at the 10 min time setting except versus Neuwave LK15 and Eco. Emprint produced ablation zones that were also significantly more spherical (highest SI) than the single-probe ablations from all other manufacturers. No statistical differences were found for ablation shape or SAD between the single-probe protocols for Emprint and the three-probe protocols for Neuwave. (4) Conclusions: The new Emprint HP system achieved large and spherical ablation zones relative to other 2.45 GHz MWA systems.
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Affiliation(s)
- Terrence C. H. Hui
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Guo Yuan How
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Michelle S. M. Chim
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Uei Pua
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore 308433, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
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Jin X, Feng Y, Zhu R, Qian L, Yang Y, Yu Q, Zou Z, Li W, Liu Y, Qian Z. Temperature control and intermittent time-set protocol optimization for minimizing tissue carbonization in microwave ablation. Int J Hyperthermia 2022; 39:868-879. [PMID: 35858640 DOI: 10.1080/02656736.2022.2075041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
PURPOSE The charring tissue formation in the ablated lesion during the microwave ablation (MWA) of tumors would induce various unwanted inflammatory responses. This paper aimed to deliver appropriate thermal dose for effective ablations while preventing tissue carbonization by optimizing the treatment protocol during MWA with the set combinations of temperature control and pulsed microwave energy delivery. MATERIAL AND METHODS The thermal phase transition of ex vivo porcine liver tissues were recorded by differential scanning calorimetry (DSC) to determine the temperature threshold during microwave output control. MWA was performed by an in-house built system with the ease of microwave output parameter adjustment and real-time temperature monitoring. The effects of continuous and pulsed microwave deliveries as well as various intermittent time-set of MWA were evaluated by measuring the dimensions of the coagulation zone and the carbonization zone. RESULTS The DSC scans demonstrated that the ex vivo porcine liver tissues have been in a state of endothermic heat during the heating process, where the maximum absorbed heat occurred at the temperature of 105 °C ± 5 °C. The temperature control during MWA resulted in effective coagulative necrosis while preventing tissue carbonization, after setting 100 °C as the upper threshold temperature and 60 °C as the lower threshold. Both the numerical simulation and ex vivo experiments have shown that, upon the optimization of the time-set parameters in the periodic intermittent pulsed microwave output, the tissue carbonization was significantly diminished. CONCLUSION This study developed a straight-forward anti-carbonization strategy in MWA by modulating the pulsing mode and intermittent time. The programmed protocols of intermittent pulsing MWA have demonstrated its potentials toward future expansion of MWA technology in clinical application.
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Affiliation(s)
- Xiaofei Jin
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Yu Feng
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Roujun Zhu
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Lu Qian
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Yamin Yang
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Qindong Yu
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Zhihan Zou
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Weitao Li
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Yangyang Liu
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Zhiyu Qian
- Department of Biomedical Engineering, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
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Zanus G, Tagliente G, Rossi S, Bonis A, Zambon M, Scopelliti M, Brizzolari M, Grossi U, Romano M, Finotti M. Pulsed Microwave Liver Ablation: An Additional Tool to Treat Hepatocellular Carcinoma. Cancers (Basel) 2022; 14:cancers14030748. [PMID: 35159014 PMCID: PMC8833939 DOI: 10.3390/cancers14030748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/26/2022] [Accepted: 01/29/2022] [Indexed: 12/15/2022] Open
Abstract
Simple Summary Hepatocellular carcinoma (HCC) is the seventh most frequent neoplasm and the second most common oncologic cause of death, mostly in patients with end-stage liver disease. HCC treatment is complex and different solutions are available, ranging from liver transplants to local therapies. In this study, we analyze the role of pulsed microwave liver ablation as an additional treatment option. Abstract This study aimed to analyze the outcomes of HCC patients treated with a novel technique—pulsed microwave ablation (MWA)—in terms of safety, local tumor progression (LTP), intrahepatic recurrence (IHR), and overall survival (OS). A total of 126 pulsed microwave procedures have been performed in our center. We included patients with mono- or multifocal HCC (BCLC 0 to D). The LTP at 12 months was 9.9%, with an IHR rate of 27.8% at one year. Survival was 92.0% at 12 months with 29.4% experiencing post-operative complications (28.6% Clavien–Dindo 1–2, 0.8% Clavien–Dindo 3–4). Stratifying patients by BCLC, we achieved BCLC 0, A, B, C, and D survival rates of 100%, 93.2%, 93.3%, 50%, and 100%, respectively, at one year, which was generally superior to or in line with the expected survival rates among patients who are started on standard treatment. The pulsed MWA technique is safe and effective. The technique can be proposed not only in patients with BCLC A staging but also in the highly selected cases of BCLC B, C, and D, confirming the importance of the concept of stage migration. This procedure, especially if performed with a minimally invasive technique (laparoscopic or percutaneous), is repeatable with a short postoperative hospital stay.
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Affiliation(s)
- Giacomo Zanus
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Giovanni Tagliente
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Serena Rossi
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Alessandro Bonis
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Mattia Zambon
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Michele Scopelliti
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Marco Brizzolari
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Ugo Grossi
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Maurizio Romano
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
| | - Michele Finotti
- 4th Surgery Unit, Regional Hospital Treviso, University of Padua, DISCOG, 31100 Padua, Italy; (G.Z.); (G.T.); (S.R.); (A.B.); (M.Z.); (M.S.); (M.B.); (U.G.); (M.R.)
- Baylor Scott & White Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX 75204, USA
- Correspondence:
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Chelales E, Morhard R, Nief C, Crouch B, Everitt JI, Sag AA, Ramanujam N. Radiologic-pathologic analysis of increased ethanol localization and ablative extent achieved by ethyl cellulose. Sci Rep 2021; 11:20700. [PMID: 34667252 PMCID: PMC8526742 DOI: 10.1038/s41598-021-99985-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 09/29/2021] [Indexed: 12/24/2022] Open
Abstract
Ethanol provides a rapid, low-cost ablative solution for liver tumors with a small technological footprint but suffers from uncontrolled diffusion in target tissue, limiting treatment precision and accuracy. Incorporating the gel-forming polymer ethyl cellulose to ethanol localizes the distribution. The purpose of this study was to establish a non-invasive methodology based on CT imaging to quantitatively determine the relationship between the delivery parameters of the EC-ethanol formulation, its distribution, and the corresponding necrotic volume. The relationship of radiodensity to ethanol concentration was characterized with water-ethanol surrogates. Ex vivo EC-ethanol ablations were performed to optimize the formulation (n = 6). In vivo ablations were performed to compare the optimal EC-ethanol formulation to pure ethanol (n = 6). Ablations were monitored with CT and ethanol distribution volume was quantified. Livers were removed, sectioned and stained with NADH-diaphorase to determine the ablative extent, and a detailed time-course histological study was performed to assess the wound healing process. CT imaging of ethanol-water surrogates demonstrated the ethanol concentration-radiodensity relationship is approximately linear. A concentration of 12% EC in ethanol created the largest distribution volume, more than eight-fold that of pure ethanol, ex vivo. In vivo, 12% EC-ethanol was superior to pure ethanol, yielding a distribution volume three-fold greater and an ablation zone six-fold greater than pure ethanol. Finally, a time course histological evaluation of the liver post-ablation with 12% EC-ethanol and pure ethanol revealed that while both induce coagulative necrosis and similar tissue responses at 1-4 weeks post-ablation, 12% EC-ethanol yielded a larger ablation zone. The current study demonstrates the suitability of CT imaging to determine distribution volume and concentration of ethanol in tissue. The distribution volume of EC-ethanol is nearly equivalent to the resultant necrotic volume and increases distribution and necrosis compared to pure ethanol.
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Affiliation(s)
- Erika Chelales
- Department of Biomedical Engineering, Duke University, Durham, NC, USA.
| | - Robert Morhard
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Corrine Nief
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Brian Crouch
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Jeffrey I Everitt
- Department of Pathology, Duke University Medical Center, Durham, NC, USA
| | - Alan Alper Sag
- Division of Vascular and Interventional Radiology, Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Nirmala Ramanujam
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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Radosevic A, Prieto D, Burdío F, Berjano E, Prakash P, Trujillo M. Short pulsed microwave ablation: computer modeling and ex vivo experiments. Int J Hyperthermia 2021; 38:409-420. [PMID: 33719808 DOI: 10.1080/02656736.2021.1894358] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
PURPOSE To study the differences between continuous and short-pulse mode microwave ablation (MWA). METHODS We built a computational model for MWA including a 200 mm long and 14 G antenna from Amica-Gen and solved an electromagnetic-thermal coupled problem using COMSOL Multiphysics. We compared the coagulation zone (CZ) sizes created with pulsed and continuous modes under ex vivo and in vivo conditions. The model was used to compare long vs. short pulses, and 1000 W high-powered short pulses. Ex vivo experiments were conducted to validate the model. RESULTS The computational models predicted the axial diameter of the CZ with an error of 2-3% and overestimated the transverse diameter by 9-11%. For short pulses, the ex vivo computer modeling results showed a trend toward larger CZ when duty cycles decreases. In general, short pulsed mode yielded higher CZ diameters and volumes than continuous mode, but the differences were not significant (<5%), as in terms of CZ sphericity. The same trends were observed in the simulations mimicking in vivo conditions. Both CZ diameter and sphericity were similar with short and long pulses. Short 1000 W pulses produced smaller sphericity and similar CZ sizes under in vivo and ex vivo conditions. CONCLUSIONS The characteristics of the CZ created by continuous and pulsed MWA show no significant differences from ex vivo experiments and computer simulations. The proposed idea of enlarging coagulation zones and improving their sphericity in pulsed mode was not evident in this study.
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Affiliation(s)
- Aleksandar Radosevic
- Department of Radiology, Hospital del Mar, Universitat Pompeu Fabra, Barcelona, Spain
| | - Diego Prieto
- BioMIT, Department of Applied Mathematics, Universitat Politècnica de València, Valencia, Spain
| | | | - Enrique Berjano
- BioMIT, Department of Electronic Engineering, Universitat Politècnica de València, Valencia, Spain
| | - Punit Prakash
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USA
| | - Macarena Trujillo
- BioMIT, Department of Applied Mathematics, Universitat Politècnica de València, Valencia, Spain
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Huang H, Zhang L, Moser MAJ, Zhang W, Zhang B. A review of antenna designs for percutaneous microwave ablation. Phys Med 2021; 84:254-264. [PMID: 33773908 DOI: 10.1016/j.ejmp.2021.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 03/03/2021] [Accepted: 03/06/2021] [Indexed: 12/15/2022] Open
Abstract
Microwave (MW) antenna is a key element in microwave ablation (MWA) treatments as the means that energy is delivered in a focused manner to the tumor and its surrounding area. The energy delivered results in a rise in temperature to a lethal level, resulting in cell death in the ablation zone. The delivery of energy and hence the success of MWA is closely dependent on the structure of the antennas. Therefore, three design criteria, such as expected ablation zone pattern, efficiency of energy delivery, and minimization of the diameter of the antennas have been the focus along the evolution of the MW antenna. To further improve the performance of MWA in the treatment of various tumors through inventing novel antennas, this article reviews the state-of-the-art and summarizes the development of MW antenna designs regarding the three design criteria.
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Affiliation(s)
- Hangming Huang
- Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, China
| | - Lifeng Zhang
- Department of General Surgery, the First Affiliated Hospital of Soochow University,Soochow University, Jiangsu, China
| | - Michael A J Moser
- Department of Surgery, College of Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Wenjun Zhang
- Division of Biomedical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, Canada
| | - Bing Zhang
- Energy-based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, China.
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