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Boregowda G, Mariappan P. Effect of high blood flow on heat distribution and ablation zone during microwave ablation-numerical approach. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2024:e3835. [PMID: 38800993 DOI: 10.1002/cnm.3835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/29/2024] [Accepted: 05/04/2024] [Indexed: 05/29/2024]
Abstract
Microwave ablation has become a viable alternative for cancer treatment for patients who cannot undergo surgery. During this procedure, a single-slot coaxial antenna is employed to effectively deliver microwave energy to the targeted tissue. The success of the treatment was measured by the amount of ablation zone created during the ablation procedure. The significantly large blood vessel placed near the antenna causes heat dissipation by convection around the blood vessel. The heat sink effect could result in insufficient ablation, raising the risk of local tumor recurrence. In this study, we investigated the heat loss due to large blood vessels and the relationship between blood velocity and temperature distribution. The hepatic artery, with a diameter of 4 mm and a height of 50 mm and two branches, is considered in the computational domain. The temperature profile, localized tissue contraction, and ablation zones were simulated for initial blood velocities 0.05, 0.1, and 0.16 m/s using the 3D Pennes bio-heat equation, temperature-time dependent model, and cell death model, respectively. Temperature-dependent blood velocity is modeled using the Navier-Stokes equation, and the fluid-solid interaction boundary is treated as a convective boundary. For discretization, we utilizedH curl Ω $$ H\left(\operatorname{curl},\Omega \right) $$ elements for the wave propagation model,H 1 Ω $$ {H}^1\left(\Omega \right) $$ elements for the Pennes bio-heat model, andH 1 Ω 3 × L 0 2 Ω $$ {\left({H}^1\left(\Omega \right)\right)}^3\times {L}_0^2\left(\Omega \right) $$ elements for the Navier-Stokes equation, whereΩ $$ \Omega $$ represents the computational domain. The simulated results show that blood vessels and blood velocity have a significant impact on temperature distribution, tissue contraction, and the volume of the ablation zone.
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Affiliation(s)
- Gangadhara Boregowda
- Department of Mathematics and Statistics, Indian Institute of Technology Tirupati, Tirupati, India
| | - Panchatcharam Mariappan
- Department of Mathematics and Statistics, Indian Institute of Technology Tirupati, Tirupati, India
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2
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Hübner F, Klaus M, Siedow N, Leithäuser C, Vogl TJ. CT-based evaluation of tissue expansion in cryoablation of ex vivo kidney. BIOMED ENG-BIOMED TE 2024; 69:211-217. [PMID: 37924274 DOI: 10.1515/bmt-2023-0174] [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: 05/06/2023] [Accepted: 10/11/2023] [Indexed: 11/06/2023]
Abstract
OBJECTIVES To evaluate tissue expansion during cryoablation, the displacement of markers in ex vivo kidney tissue was determined using computed tomographic (CT) imaging. METHODS CT-guided cryoablation was performed in nine porcine kidneys over a 10 min period. Markers and fiber optic temperature probes were positioned perpendicular to the cryoprobe shaft in an axial orientation. The temperature measurement was performed simultaneously with the acquisitions of the CT images in 5 s intervals. The distance change of the markers to the cryoprobe was determined in each CT image and equated to the measured temperature at the marker. RESULTS The greatest increase in the distance between the markers and the cryoprobe was observed in the initial phase of cryoablation. The maximum displacement of the markers was determined to be 0.31±0.2 mm and 2.8±0.02 %, respectively. CONCLUSIONS The mean expansion of ex vivo kidney tissue during cryoablation with a single cryoprobe is 0.31±0.2 mm. The results can be used for identification of basic parameters for optimization of therapy planning.
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Affiliation(s)
- Frank Hübner
- Institute of Diagnostic and Interventional Radiology, University Hospital, Goethe University Frankfurt, Frankfurt, Germany
| | - Moritz Klaus
- Institute of Diagnostic and Interventional Radiology, University Hospital, Goethe University Frankfurt, Frankfurt, Germany
| | - Norbert Siedow
- Fraunhofer Institute for Industrial Mathematics (ITWM), Kaiserslautern, Germany
| | | | - Thomas Josef Vogl
- Institute of Diagnostic and Interventional Radiology, University Hospital, Goethe University Frankfurt, Frankfurt, Germany
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Hendriks P, Boel F, Oosterveer TTM, Broersen A, de Geus-Oei LF, Dijkstra J, Burgmans MC. Ablation margin quantification after thermal ablation of malignant liver tumors: How to optimize the procedure? A systematic review of the available evidence. Eur J Radiol Open 2023; 11:100501. [PMID: 37405153 PMCID: PMC10316004 DOI: 10.1016/j.ejro.2023.100501] [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: 03/31/2023] [Revised: 06/21/2023] [Accepted: 06/23/2023] [Indexed: 07/06/2023] Open
Abstract
Introduction To minimize the risk of local tumor progression after thermal ablation of liver malignancies, complete tumor ablation with sufficient ablation margins is a prerequisite. This has resulted in ablation margin quantification to become a rapidly evolving field. The aim of this systematic review is to give an overview of the available literature with respect to clinical studies and technical aspects potentially influencing the interpretation and evaluation of ablation margins. Methods The Medline database was reviewed for studies on radiofrequency and microwave ablation of liver cancer, ablation margins, image processing and tissue shrinkage. Studies included in this systematic review were analyzed for qualitative and quantitative assessment methods of ablation margins, segmentation and co-registration methods, and the potential influence of tissue shrinkage occurring during thermal ablation. Results 75 articles were included of which 58 were clinical studies. In most clinical studies the aimed minimal ablation margin (MAM) was ≥ 5 mm. In 10/31 studies, MAM quantification was performed in 3D rather than in three orthogonal image planes. Segmentations were performed either semi-automatically or manually. Rigid and non-rigid co-registration algorithms were used about as often. Tissue shrinkage rates ranged from 7% to 74%. Conclusions There is a high variability in ablation margin quantification methods. Prospectively obtained data and a validated robust workflow are needed to better understand the clinical value. Interpretation of quantified ablation margins may be influenced by tissue shrinkage, as this may cause underestimation.
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Affiliation(s)
- Pim Hendriks
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Fleur Boel
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Timo TM Oosterveer
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Alexander Broersen
- LKEB Laboratory of Clinical and Experimental Imaging, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Lioe-Fee de Geus-Oei
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
- Biomedical Photonic Imaging Group, University of Twente, the Netherlands
| | - Jouke Dijkstra
- LKEB Laboratory of Clinical and Experimental Imaging, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Mark C Burgmans
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
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Tsochatzis A, Charalampopoulos G, Tzelves L, Velonakis G, Kelekis A, Kelekis N, Filippiadis DK. Percutaneous microwave ablation of hepatic tumors: is there an impact of cirrhotic liver parenchyma upon the volume and short-term assessment of the ablation zone? Br J Radiol 2023; 96:20230383. [PMID: 37750857 PMCID: PMC10646625 DOI: 10.1259/bjr.20230383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 09/10/2023] [Accepted: 09/16/2023] [Indexed: 09/27/2023] Open
Abstract
OBJECTIVE To retrospectively compare and evaluate ablation zone volume and its reduction from baseline to 1 month follow-up post-percutaneous microwave ablation (MWA) between healthy and cirrhotic liver parenchyma. METHODS Institutional database research identified 84 patients (118 hepatic tumors) who underwent percutaneous MWA with the same system. Caudal-right lobe ratio was applied to distinguish cirrhotic (n = 51) and healthy (n = 67) group; ITK-SNAP software was used to quantify ablation zone volume. Long (LAD) and short 1 (SAD-1) and 2 (SAD-2) axis, tumor size diameter (mm) and volume (cm³) of the ablation zones were evaluated for each treated lesion in both groups at baseline (immediately post-ablation) and at 1 month follow-up. RESULTS There was no significant difference comparing ablation zone volumes at baseline (healthy group: mean ablation volume 14.84 cm³ vs cirrhotic group: mean ablation volume 17.85 cm³, p = 0.31) and 1 month post-ablation (healthy group: mean ablation volume 9.15 cm³ vs cirrhotic group: mean ablation volume 11.58 cm³, p = 0.24). When both "healthy" and "cirrhotic" liver group were evaluated independently, there was a significant difference of ablation volumes reduction (p-value < 0.001) from baseline to 1 month follow-up. When both groups were compared based on reduction (35.12-38.34%) there was no significant difference in ablation zone volumes (p-value = 0.77). CONCLUSION Percutaneous MWA results in ablation zones of a comparable volume in both healthy and cirrhotic liver parenchyma. Both cirrhotic and healthy liver parenchyma experience a similar significant reduction of ablation zone volume at 1 month post-therapy. ADVANCES IN KNOWLEDGE STATEMENT This study evaluates and compares the volume of the ablation zone after MWA between healthy and cirrhotic liver parenchyma from baseline to 1 month follow-up and attempts to identify potential differences. It is the first study to demonstrate significant shrinkage of ablation volumes in healthy livers as compared to cirrhotic livers after 4 weeks of follow-up. The results of this study can help us understand the effect of MWA when applied in different backgrounds of liver parenchyma, which could lead to different treatment planning.
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Affiliation(s)
- Athanasios Tsochatzis
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - George Charalampopoulos
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Lazaros Tzelves
- Department of Urology, Uro-Oncology, University College of London Hospitals, NHS Trust, London, United Kingdom
| | - George Velonakis
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Alexios Kelekis
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Nikolaos Kelekis
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Dimitrios K Filippiadis
- 2nd Department of Radiology, University General Hospital "ATTIKON", Medical School, National and Kapodistrian University of Athens, Athens, Greece
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Boregowda G, Mariappan P. 3D modeling of vector/edge finite element method for multi-ablation technique for large tumor-computational approach. PLoS One 2023; 18:e0289262. [PMID: 37506084 PMCID: PMC10381062 DOI: 10.1371/journal.pone.0289262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Microwave ablation (MWA) is a cancer thermal ablation treatment that uses electromagnetic waves to generate heat within the tissue. The goal of this treatment is to eliminate tumor cells while leaving healthy cells unharmed. During MWA, excess heat generation can kill healthy cells. Hence, mathematical models and numerical techniques are required to analyze the heat distribution in the tissue before the treatment. The aim of this research is to explain the implementation of the 3D vector finite element method in a wave propagation model that simulates the specific absorption rate in the liver. The 3D Nedelec elements from H(curl; Ω) space are used to discretize the wave propagation model, and this implementation is helpful in solving many real-world problems that involve electromagnetic propagation with perfect conducting and absorbing boundary conditions. One of the difficulties in ablation treatment is creating a large ablation zone for a large tumor (diameter greater than 3 cm) in a short period of time with minimum damage to the surrounding tissue. This article addresses the aforementioned issue by introducing four antennas into the different places of the tumor sequentially and producing heat uniformly over the tumor. The results demonstrated that 95.5% of the tumor cells were killed with minimal damage to the healthy cells when the heating time was increased to 4 minutes at each position. Subsequently, we studied the temperature distribution and localised tissue contraction in the tissue using the three-dimensional bio-heat equation and temperature-time dependent model, respectively. The local tissue contraction is measured at arbitrary points in the domain and is more noticeable at temperatures higher than 102°C. The thermal damage in the liver during MWA treatment is investigated using the three-state cell death model. The system of partial differential equations is solved numerically due to the complex geometry of the domain, and the results are compared with experimental data to validate the models and parameters.
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Affiliation(s)
- Gangadhara Boregowda
- Department of Mathematics and Statistics, Indian Institute of Technology Tirupati, Andhra Pradesh, India
| | - Panchatcharam Mariappan
- Department of Mathematics and Statistics, Indian Institute of Technology Tirupati, Andhra Pradesh, India
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6
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Microwave ablation trocar for ablating cancerous tumors: a numerical analysis. Med Biol Eng Comput 2023; 61:1113-1131. [PMID: 36680706 DOI: 10.1007/s11517-023-02781-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 01/11/2023] [Indexed: 01/22/2023]
Abstract
Microwave ablation (MWA) is a newly developing minimally invasive thermal therapies technology. The ablation region obtained during MWA mainly depends on the type and efficiency of the trocar as well as the energy transfer from the generator to the biological tissue. In the present article, a novel trocar for MWA therapies has been proposed. A 3-dimensional tumor-embedded hepatic gland ablated with the novel MWA trocar has been numerically analyzed using finite element method-based software. The novel trocar consists of a flexible dual tine supplied with a microwave power of 15 W at 2.45/6 GHz for an ablation time of 10 min for all the cases. Various combinations of supplied energy and deploying lengths result in tumor ablations ranging from 2.7 to 4 cm in diameter. Supplying energy at high frequency (6 GHz) to the trocar results in ablating tumors (> 4 cm) with spherical ablation region. The novel trocar generated large ablation regions which are 2-3 times bigger than the tumors obtained using existing single-slot non-cooled trocars. This research on novel trocar may help clinicians in treating large size tumors of symmetric and asymmetric shapes by overcoming the problem associated with precise position of trocar into the tissue.
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Ghahramani Z E, Grimm PD, Eary KJ, Swearengen MP, Dayavansha EGSK, Mast TD. Three-dimensional echo decorrelation monitoring of radiofrequency ablation in ex vivo bovine liver. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:3907. [PMID: 35778168 PMCID: PMC9187351 DOI: 10.1121/10.0011641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 05/14/2022] [Accepted: 05/23/2022] [Indexed: 06/03/2023]
Abstract
Three-dimensional (3D) echo decorrelation imaging was investigated for monitoring radiofrequency ablation (RFA) in ex vivo bovine liver. RFA experiments (N = 14) were imaged by 3D ultrasound using a matrix array, with in-phase and quadrature complex echo volumes acquired about every 11 s. Tissue specimens were then frozen at -80 °C, sectioned, and semi-automatically segmented. Receiver operating characteristic (ROC) curves were constructed for assessing ablation prediction performance of 3D echo decorrelation with three potential normalization approaches, as well as 3D integrated backscatter (IBS). ROC analysis indicated that 3D echo decorrelation imaging is potentially a good predictor of local RFA, with the best prediction performance observed for globally normalized decorrelation. Tissue temperatures, recorded by four thermocouples integrated into the RFA probe, showed good correspondence with spatially averaged decorrelation and statistically significant but weak correlation with measured echo decorrelation at the same spatial locations. In tests predicting ablation zones using a weighted K-means clustering approach, echo decorrelation performed better than IBS, with smaller root mean square volume errors and higher Dice coefficients relative to measured ablation zones. These results suggest that 3D echo decorrelation and IBS imaging are capable of real-time monitoring of thermal ablation, with potential application to clinical treatment of liver tumors.
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Affiliation(s)
- E Ghahramani Z
- Department of Biomedical Engineering, University of Cincinnati, Ohio 45267-0586, USA
| | - P D Grimm
- Department of Biomedical Engineering, University of Cincinnati, Ohio 45267-0586, USA
| | - K J Eary
- Department of Biomedical Engineering, University of Cincinnati, Ohio 45267-0586, USA
| | - M P Swearengen
- Department of Biomedical Engineering, University of Cincinnati, Ohio 45267-0586, USA
| | | | - T D Mast
- Department of Biomedical Engineering, University of Cincinnati, Ohio 45267-0586, USA
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Bianchi L, Cavarzan F, Ciampitti L, Cremonesi M, Grilli F, Saccomandi P. Thermophysical and mechanical properties of biological tissues as a function of temperature: a systematic literature review. Int J Hyperthermia 2022; 39:297-340. [DOI: 10.1080/02656736.2022.2028908] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Leonardo Bianchi
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
| | - Fabiana Cavarzan
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
| | - Lucia Ciampitti
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
| | - Matteo Cremonesi
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
| | - Francesca Grilli
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
| | - Paola Saccomandi
- Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy
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Lee J, Rhim H, Lee MW, Kang TW, Song KD, Lee JK. Direction of Tissue Contraction after Microwave Ablation: A Comparative Experimental Study in Ex Vivo Bovine Liver. Korean J Radiol 2022; 23:42-51. [PMID: 34983092 PMCID: PMC8743151 DOI: 10.3348/kjr.2021.0134] [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: 05/03/2020] [Revised: 07/11/2021] [Accepted: 08/16/2021] [Indexed: 11/23/2022] Open
Abstract
Objective This study aimed to investigate the direction of tissue contraction after microwave ablation in ex vivo bovine liver models. Materials and Methods Ablation procedures were conducted in a total of 90 sites in ex vivo bovine liver models, including the surface (n = 60) and parenchyma (n = 30), to examine the direction of contraction of the tissue in the peripheral and central regions from the microwave antenna. Three commercially available 2.45-GHz microwave systems (Emprint, Neuwave, and Surblate) were used. For surface ablation, the lengths of two overlapped square markers were measured after 2.5- and 5-minutes ablations (n = 10 ablations for each system for each ablation time). For parenchyma ablation, seven predetermined distances between the markers were measured on the cutting plane after 5- and 10-minutes ablations (n = 5 ablations for each system for each ablation time). The contraction in the radial and longitudinal directions and the sphericity index (SI) of the ablation zones were compared between the three systems using analysis of variance. Results In the surface ablation experiment, the mean longitudinal contraction ratio and SI from a 5-minutes ablation using the Emprint, Neuwave, and Surblate systems were 28.92% and 1.04, 20.10% and 0.53, and 24.90% and 0.45, respectively (p < 0.001). A positive correlation between longitudinal contraction and SI was noted, and a similar radial contraction was observed. In the parenchyma ablation experiment, the mean longitudinal contraction ratio and SI from a 10-minutes ablation using the three pieces of equipment were 38.60% and 1.06, 32.45% and 0.61, and 28.50% and 0.50, respectively (p < 0.001). There was a significant difference in the longitudinal contraction properties, whereas there was no significant difference in the radial contraction properties. Conclusion The degree of longitudinal contraction showed significant differences depending on the microwave ablation equipment, which may affect the SI of the ablation zone.
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Affiliation(s)
- Junhyok Lee
- Department of Medical Device Management and Research, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Hyunchul Rhim
- Department of Medical Device Management and Research, SAIHST, Sungkyunkwan University, Seoul, Korea.,Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
| | - Min Woo Lee
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Tae Wook Kang
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyoung Doo Song
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jeong Kyong Lee
- Department of Radiology, Mokdong Hospital, Ewha Womans University, School of Medicine, Seoul, Korea
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Qu Z, Tang J, Sablani SS, Ross CF, Sankaran S, Shah DH. Quality changes in chicken livers during cooking. Poult Sci 2021; 100:101316. [PMID: 34329987 PMCID: PMC8335660 DOI: 10.1016/j.psj.2021.101316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/22/2021] [Accepted: 06/01/2021] [Indexed: 11/30/2022] Open
Abstract
Raw chicken livers are often contaminated with Campylobacter and Salmonella. Cooking is considered the last defense of pathogen control for meals containing chicken livers. However, consumers' preference for pink color and a creamy texture as desired attributes in preparing liver pâté may lead to inadequate cooking, thereby increasing the risk of foodborne illness. This study aimed to investigate the effects of different cooking conditions (60-90°C, 0-65 min) on quality changes in frozen and fresh chicken livers and develop cooking recommendations to produce safe liver products with desired qualities. Frozen storage reduced the water holding capacity of raw chicken livers and led to more cooking loss (reduction in the weight of liver pieces during cooking) and area shrinkage after heating. The cooking loss and area shrinkage increased with increasing heating time and temperature, following the first-order fractional model. Compared with fresh livers, the shear resistance for cutting through the cooked livers increased after heating at 73.9°C to 90°C and decreased at 60°C, whereas the livers heated at 70°C had shear resistance (~4.5 N/g) similar to the fresh liver, regardless of the heating times used in this study. Heating resulted in color changes in livers, shifting from red hue (0°) toward yellow hue (90°), as characterized by the increased hue angles after heating. Cooking livers to an internal temperature of 70°C to 73.9°C and hold for 101 to 26 s is recommended for food processing plants or restaurants to prepare ready-to-eat meals containing chicken livers to achieve microbial safety with respect to Salmonella and provide cooked livers with desired texture and pink color.
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Affiliation(s)
- Zhi Qu
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, 99164-6120, USA
| | - Juming Tang
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, 99164-6120, USA.
| | - Shyam S Sablani
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, 99164-6120, USA
| | - Carolyn F Ross
- School of Food Science, Washington State University, Pullman, WA, 99164-6120, USA
| | - Sindhuja Sankaran
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, 99164-6120, USA
| | - Devendra H Shah
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164-7040, USA
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Pohlman RM, Hinshaw JL, Ziemlewicz TJ, Lubner MG, Wells SA, Lee FT, Alexander ML, Wergin KL, Varghese T. Differential Imaging of Liver Tumors before and after Microwave Ablation with Electrode Displacement Elastography. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:2138-2156. [PMID: 34011451 PMCID: PMC8243838 DOI: 10.1016/j.ultrasmedbio.2021.03.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 03/18/2021] [Accepted: 03/23/2021] [Indexed: 05/17/2023]
Abstract
Liver cancer is a leading cause of cancer-related deaths; however, primary treatment options such as surgical resection and liver transplant may not be viable for many patients. Minimally invasive image-guided microwave ablation (MWA) provides a locally effective treatment option for these patients with an impact comparable to that of surgery for both cancer-specific and overall survival. MWA efficacy is correlated with accurate image guidance; however, conventional modalities such as B-mode ultrasound and computed tomography have limitations. Alternatively, ultrasound elastography has been used to demarcate post-ablation zones, yet has limitations for pre-ablation visualization because of variability in strain contrast between cancer types. This study attempted to characterize both pre-ablation tumors and post-ablation zones using electrode displacement elastography (EDE) for 13 patients with hepatocellular carcinoma or liver metastasis. Typically, MWA ablation margins of 0.5-1.0 cm are desired, which are strongly correlated with treatment efficacy. Our results revealed an average estimated ablation margin inner quartile range of 0.54-1.21 cm with a median value of 0.84 cm. These treatment margins lie within or above the targeted ablative margin, indicating the potential to use EDE for differentiating index tumors and ablated zones during clinical ablations. We also obtained a high correlation between corresponding segmented cross-sectional areas from contrast-enhanced computed tomography, the current clinical gold standard, when compared with EDE strain images, with r2 values of 0.97 and 0.98 for pre- and post-ablation regions.
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Affiliation(s)
- Robert M Pohlman
- Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
| | - James L Hinshaw
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Timothy J Ziemlewicz
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Meghan G Lubner
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Shane A Wells
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Fred T Lee
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Marci L Alexander
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Kelly L Wergin
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Tomy Varghese
- Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
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12
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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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Reimer RP, Hokamp NG, Niehoff J, Zopfs D, Lennartz S, Heidar M, Wahba R, Stippel D, Maintz D, dos Santos DP, Wybranski C. Value of spectral detector computed tomography for the early assessment of technique efficacy after microwave ablation of hepatocellular carcinoma. PLoS One 2021; 16:e0252678. [PMID: 34129650 PMCID: PMC8205161 DOI: 10.1371/journal.pone.0252678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 05/19/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES To investigate whether virtual monoenergetic images (VMI) and iodine maps derived from spectral detector computed tomography (SDCT) improve early assessment of technique efficacy in patients who underwent microwave ablation (MWA) for hepatocellular carcinoma (HCC) in liver cirrhosis. METHODS This retrospective study comprised 39 patients with 49 HCC lesions treated with MWA. Biphasic SDCT was performed 7.7±4.0 days after ablation. Conventional images (CI), VMI and IM were reconstructed. Signal- and contrast-to-noise ratio (SNR, CNR) in the ablation zone (AZ), hyperemic rim (HR) and liver parenchyma were calculated using regions-of-interest analysis and compared between CI and VMI between 40-100 keV. Iodine concentration and perfusion ratio of HR and residual tumor (RT) were measured. Two readers evaluated subjective contrast of AZ and HR, technique efficacy (complete vs. incomplete ablation) and diagnostic confidence at determining technique efficacy. RESULTS Attenuation of liver parenchyma, HR and RT, SNR of liver parenchyma and HR, CNR of AZ and HR were significantly higher in low-keV VMI compared to CI (all p<0.05). Iodine concentration and perfusion ratio differed significantly between HR and RT (all p<0.05; e.g. iodine concentration, 1.6±0.5 vs. 2.7±1.3 mg/ml). VMI50keV improved subjective AZ-to-liver contrast, HR-to-liver contrast, visualization of AZ margin and vessels adjacent to AZ compared to CI (all p<0.05). Diagnostic accuracy for detection of incomplete ablation was slightly higher in VMI50keV compared to CI (0.92 vs. 0.89), while diagnostic confidence was significantly higher in VMI50keV (p<0.05). CONCLUSIONS Spectral detector computed tomography derived low-keV virtual monoenergetic images and iodine maps provide superior early assessment of technique efficacy of MWA in HCC compared to CI.
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Affiliation(s)
- Robert Peter Reimer
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
- * E-mail:
| | - Nils Große Hokamp
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Julius Niehoff
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - David Zopfs
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Simon Lennartz
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
- Department of Radiology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Mariam Heidar
- Faculty of Medicine, University Cologne, Cologne, Germany
| | - Roger Wahba
- Faculty of Medicine and University Hospital Cologne, Department of General-, Visceral, Cancer and Transplant Surgery, University of Cologne, Cologne, Germany
| | - Dirk Stippel
- Faculty of Medicine and University Hospital Cologne, Department of General-, Visceral, Cancer and Transplant Surgery, University of Cologne, Cologne, Germany
| | - David Maintz
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Daniel Pinto dos Santos
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Christian Wybranski
- Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
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Meloni MF, Francica G, Chiang J, Coltorti A, Danzi R, Laeseke PF. Use of Contrast-Enhanced Ultrasound in Ablation Therapy of HCC: Planning, Guiding, and Assessing Treatment Response. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2021; 40:879-894. [PMID: 32936485 DOI: 10.1002/jum.15471] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 07/23/2020] [Indexed: 06/11/2023]
Abstract
Contrast-enhanced ultrasonography (CEUS) plays an important role in the management of patients treated with ablation therapies, in the diagnostic, therapeutic and monitoring phases. Compared to contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging, CEUS presents several advantages in imaging HCC, including real time imaging capability, high sensitivity for tumor vascularity, absence of renal toxicity, no ionizing radiation, repeatability of injections, good compliance by the patient and low cost. The purpose of this review is to evaluate the role of CEUS in the management of the patients with HCC treated with ablation therapies and describe how in our protocol CEUS is integrated with the other imaging modalities such as contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging.
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Affiliation(s)
- Maria Franca Meloni
- Radiology Department, University of Pavia, Italy and Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
| | - Giampiero Francica
- Interventional Ultrasound Unit, Pineta Grande Hospital, Castel Volturno, Italy
| | - Jason Chiang
- Department of Radiology, Ronald Reagan UCLA Medical Center, Los Angeles, USA
| | - Andrea Coltorti
- Department of Radiology, Federico II University, Naples, Italy
| | - Roberta Danzi
- Department of Radiology, Pineta Grande Hospital, Castel Volturno, Italy
| | - Paul F Laeseke
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
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Tsochatzis A, Mazioti A, Iliadis G, Velonakis G, Efthymiou E, Kelekis A, Kelekis N, Filippiadis D. Percutaneous Microwave Ablation of Liver Lesions: Differences on the Sphericity Index of the Ablation Zone between Cirrhotic and Healthy Liver Parenchyma. Diagnostics (Basel) 2021; 11:diagnostics11040655. [PMID: 33916400 PMCID: PMC8066372 DOI: 10.3390/diagnostics11040655] [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: 03/20/2021] [Revised: 03/29/2021] [Accepted: 03/30/2021] [Indexed: 12/24/2022] Open
Abstract
To compare different parameters of the sphericity index of the ablation zone following microwave ablation (MWA) on cirrhotic- and healthy-liver parenchyma in a series of patients treated with the same MWA system. Institutional database research identified 46 patients (77 lesions) who underwent MWA. “Cirrhotic liver group” (CLG) included 35 hepatocellular carcinoma lesions; “healthy liver group” (HLG) included 42 metastatic lesions. The long axis (LAD), short axis 1 (SAD-1) and 2 (SAD-2), the mean SAD-1 and SAD-2 (mSAD) diameter (in mm) and the mean sphericity (mSPH) index of the ablation zones were evaluated for each treated lesion in both groups from baseline to follow-up. A mixed model analysis of variance reported significant main effect of group on SAD-1 (p = 0.023), SAD-2 (p = 0.010) and mSAD (p = 0.010), with HLG showing lower values compared to CLG. No differences were detected on the LAD (pFDR = 0.089; d = 0.45), and mSPH (pFDR = 0.148, d = 0.40) between the two groups. However, a significant main effect of time was found on LAD (p < 0.001), SAD-1 (p < 0.001), SAD-2 (p < 0.001) and mSAD (p < 0.001), with decreased values in all indices at follow-up compared to baseline. A significant group by time interaction was observed on mSPH (p = 0.044); HLG had significantly lower mSPH at follow-up where CLG did not show any significant change. Our findings indicate that although in cirrhotic liver short axis diameter of the MWA zone seems to be significantly longer, this has no effect on the sphericity index which showed no significant difference between cirrhotic vs. healthy liver lesions. On the contrary, on one month follow-up ablation zones tend to become significant more ellipsoid in healthy whilst remains stable in cirrhotic liver.
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Etoz S, Brace CL. Computed Tomography-Based Modeling of Water Vapor-Induced Changes in Permittivity During Microwave Ablation. IEEE Trans Biomed Eng 2020; 67:2427-2433. [DOI: 10.1109/tbme.2019.2962363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Ziv O, Goldberg SN, Nissenbaum Y, Sosna J, Weiss N, Azhari H. In vivo noninvasive three-dimensional (3D) assessment of microwave thermal ablation zone using non-contrast-enhanced x-ray CT. Med Phys 2020; 47:4721-4734. [PMID: 32745257 DOI: 10.1002/mp.14428] [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: 01/23/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To develop an image processing methodology for noninvasive three-dimensional (3D) quantification of microwave thermal ablation zones in vivo using x-ray computed tomography (CT) imaging without injection of a contrast enhancing material. METHODS Six microwave (MW) thermal ablation procedures were performed in three pigs. The ablations were performed with a constant heating duration of 8 min and power level of 30 W. During the procedure images from sixty 1 mm thick slices were acquired every 30 s. At the end of all ablation procedures for each pig, a contrast-enhanced scan was acquired for reference. Special algorithms for addressing challenges stemming from the 3D in vivo setup and processing the acquired images were prepared. The algorithms first rearranged the data to account for the oblique needle orientation and for breathing motion. Then, the gray level variance changes were analyzed, and optical flow analysis was applied to the treated volume in order to obtain the ablation contours and reconstruct the ablation zone in 3D. The analysis also included a special correction algorithm for eliminating artifacts caused by proximal major blood vessels and blood flow. Finally, 3D reference reconstructions from the contrast-enhanced scan were obtained for quantitative comparison. RESULTS For four ablations located >3 mm from a large blood vessel, the mean dice similarity coefficient (DSC) and the mean absolute radial discrepancy between the contours obtained from the reference contrast-enhanced images and the contours produced by the algorithm were 0.82 ± 0.03 and 1.92 ± 1.47 mm, respectively. In two cases of ablation adjacent to large blood vessels, the average DSC and discrepancy were: 0.67 ± 0.6 and 2.96 ± 2.15 mm, respectively. The addition of the special correction algorithm utilizing blood vessels mapping improved the mean DSC and the mean absolute discrepancy to 0.85 ± 0.02 and 1.19 ± 1.00 mm, respectively. CONCLUSIONS The developed algorithms provide highly accurate detailed contours in vivo (average error < 2.5 mm) and cope well with the challenges listed above. Clinical implementation of the developed methodology could potentially provide real time noninvasive 3D accurate monitoring of MW thermal ablation in-vivo, provided that the radiation dose can be reduced.
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Affiliation(s)
- Omri Ziv
- Department of Biomedical Engineering, Technion - IIT, Haifa, 32000, Israel
| | - S Nahum Goldberg
- Department of Radiology, Hadassah Medical Center, Hebrew University, Jerusalem, 91120, Israel.,Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, 02215, USA
| | - Yitzhak Nissenbaum
- Department of Radiology, Hadassah Medical Center, Hebrew University, Jerusalem, 91120, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Center, Hebrew University, Jerusalem, 91120, Israel.,Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, 02215, USA
| | - Noam Weiss
- Department of Biomedical Engineering, Technion - IIT, Haifa, 32000, Israel
| | - Haim Azhari
- Department of Biomedical Engineering, Technion - IIT, Haifa, 32000, Israel
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Use of microwave ablation for thermal treatment of solid tumors with different shapes and sizes-A computational approach. PLoS One 2020; 15:e0233219. [PMID: 32542034 PMCID: PMC7295236 DOI: 10.1371/journal.pone.0233219] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 04/30/2020] [Indexed: 12/11/2022] Open
Abstract
Microwave Ablation (MWA) is one of the most recent developments in the field of thermal therapy. This approach is an effective method for thermal tumor ablation by increasing the temperature above the normal physiological threshold to kill cancer cells with minimum side effects to surrounding organs due to rapid heat dispersive tissues. In the present study, the effects of the shape and size of the tumor on MWA are investigated. To obtain the temperature gradient, coupled bio-heat and electromagnetic equations are solved using a three-dimensional finite element method (FEM). To extract cellular response at different temperatures and times, the three-state mathematical model was employed to achieve the ablation zone size. Results show that treatment of larger tumors is more difficult than that of smaller ones. By doubling the diameter of the tumor, the percentage of dead cancer cells is reduced by 20%. For a spherical tumor smaller than 2 cm, applying 50 W input power compared to 25 W has no significant effects on treatment efficiency and only increases the risk of damage to adjacent tissues. However, for tumors larger than 2 cm, it can increase the ablation zone up to 21%. In the spherical and oblate tumors, the mean percentage of dead cells at 6 GHz is nearly 30% higher than that at 2.45GHz, but for prolate tumors, treatment efficacy is reduced by 10% at a higher frequency. Moreover, the distance between two slots in the coaxial double slot antenna is modified based on the best treatment of prolate tumors. The findings of this study can be used to choose the optimum frequency and the best antenna design according to the shape and size of the tumor.
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Singh S, Melnik R. Thermal ablation of biological tissues in disease treatment: A review of computational models and future directions. Electromagn Biol Med 2020; 39:49-88. [PMID: 32233691 DOI: 10.1080/15368378.2020.1741383] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Percutaneous thermal ablation has proven to be an effective modality for treating both benign and malignant tumours in various tissues. Among these modalities, radiofrequency ablation (RFA) is the most promising and widely adopted approach that has been extensively studied in the past decades. Microwave ablation (MWA) is a newly emerging modality that is gaining rapid momentum due to its capability of inducing rapid heating and attaining larger ablation volumes, and its lesser susceptibility to the heat sink effects as compared to RFA. Although the goal of both these therapies is to attain cell death in the target tissue by virtue of heating above 50°C, their underlying mechanism of action and principles greatly differs. Computational modelling is a powerful tool for studying the effect of electromagnetic interactions within the biological tissues and predicting the treatment outcomes during thermal ablative therapies. Such a priori estimation can assist the clinical practitioners during treatment planning with the goal of attaining successful tumour destruction and preservation of the surrounding healthy tissue and critical structures. This review provides current state-of-the-art developments and associated challenges in the computational modelling of thermal ablative techniques, viz., RFA and MWA, as well as touch upon several promising avenues in the modelling of laser ablation, nanoparticles assisted magnetic hyperthermia and non-invasive RFA. The application of RFA in pain relief has been extensively reviewed from modelling point of view. Additionally, future directions have also been provided to improve these models for their successful translation and integration into the hospital work flow.
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Affiliation(s)
- Sundeep Singh
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Roderick Melnik
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada.,BCAM - Basque Center for Applied Mathematics, Bilbao, Spain
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20
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Singh S, Melnik R. Coupled thermo-electro-mechanical models for thermal ablation of biological tissues and heat relaxation time effects. Phys Med Biol 2019; 64:245008. [PMID: 31600740 DOI: 10.1088/1361-6560/ab4cc5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Thermal ablation is a widely applied electrosurgical process in medical treatment of soft biological tissues. Numerical modeling and simulations play an important role in prediction of temperature distribution and damage volume during the treatment planning stage of associated therapies. In this contribution we report a coupled thermo-electro-mechanical model, accounting for heat relaxation time, for more accurate and precise prediction of the temperature distribution, tissue deformation and damage volume during the thermal ablation of biological tissues. Finite element solutions are obtained for most widely used percutaneous thermal ablative techniques, viz., radiofrequency ablation (RFA) and microwave ablation (MWA). Importantly, both tissue expansion and shrinkage have been considered for modeling the tissue deformation in the coupled model of high temperature thermal ablation. The coupled model takes into account the non-Fourier effects, considering both single-phase-lag (SPL) and dual-phase-lag (DPL) models of bio-heat transfer. The temperature-dependent electrical and thermal parameters, damage-dependent blood perfusion rate and phase change effect accounting for tissue vaporization have been accounted for obtaining more clinically relevant model. The proposed model predictions are found to be in good agreement against the temperature distribution and damage volume reported by previous experimental studies. The numerical simulation results revealed that the non-Fourier effects cause a decrease in the predicted temperature distribution, tissue deformation and damage volume during the high temperature thermal ablative procedures. Furthermore, the effects of different magnitudes of phase lags of the heat flux and temperature gradient on the predicted treatment outcomes of the considered thermal ablative modalities are also quantified and discussed in detail.
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Affiliation(s)
- Sundeep Singh
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, 75 University Avenue West, Waterloo, Ontario N2L 3C5, Canada. Author to whom any correspondence should be addressed
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21
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Ridouani F, Srimathveeravalli G. Percutaneous image-guided ablation: From techniques to treatments. Presse Med 2019; 48:e219-e231. [PMID: 31447333 DOI: 10.1016/j.lpm.2019.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/11/2019] [Indexed: 02/06/2023] Open
Abstract
Image-guided ablation is performed by percutaneously introducing ablation probes to deliver energy into a tumor to destroy it in a controlled and localized fashion. Ablation modalities can be broadly classified as thermal or non-thermal based on the mechanism of tumor destruction and are performed using different types of image guidance for planning, delivering and follow-up of the treatment. Ablation is performed in a minimally invasive fashion, providing greater residual organ preservation with minimal morbidity to the patient. Image-guided ablation is being used in the clinic for the treatment of primary and metastatic tumors, and this article reviews state of the art for the treatment of malignancies in the liver, lung, kidney and musculoskeletal tissue.
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Affiliation(s)
- Fourat Ridouani
- Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, USA
| | - Govindarajan Srimathveeravalli
- University of Massachusetts, Institute for Applied Life Sciences, Department of Mechanical and Industrial Engineering, Amherst, USA.
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Ruiter SJS, Heerink WJ, de Jong KP. Liver microwave ablation: a systematic review of various FDA-approved systems. Eur Radiol 2019; 29:4026-4035. [PMID: 30506218 PMCID: PMC6611060 DOI: 10.1007/s00330-018-5842-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/18/2018] [Accepted: 10/19/2018] [Indexed: 12/11/2022]
Abstract
OBJECTIVES The aim of the present study is to analyze preclinical and clinical data on the performance of the currently US Food and Drug Administration (FDA)-approved microwave ablation (MWA) systems. METHODS A review of the literature, published between January 1, 2005, and December 31, 2016, on seven FDA-approved MWA systems, was conducted. Ratio of ablation zone volume to applied energy R(AZ:E) and sphericity indices were calculated for ex vivo and in vivo experiments. RESULTS Thirty-four studies with ex vivo, in vivo, and clinical data were summarized. In total, 14 studies reporting data on ablation zone volume and applied energy were included for comparison R(AZ:E). A significant correlation between volume and energy was found for the ex vivo experiments (r = 0.85, p < 0.001) in contrast to the in vivo experiments (r = 0.54, p = 0.27). CONCLUSION Manufacturers' algorithms on microwave ablation zone sizes are based on preclinical animal experiments with normal liver parenchyma. Clinical data reporting on ablation zone volume in relation to applied energy and sphericity index during MWA are scarce and require more adequate reporting of MWA data. KEY POINTS • Clinical data reporting on the ablation zone volume in relation to applied energy during microwave ablation are scarce. • Manufacturers' algorithms on microwave ablation zone sizes are based on preclinical animal experiments with normal liver parenchyma. • Preclinical data do not predict actual clinical ablation zone volumes in patients with liver tumors.
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Affiliation(s)
- Simeon J S Ruiter
- Department of HPB Surgery and Liver Transplantation, University of Groningen, University Medical Center Groningen, Groningen, Netherlands.
| | - Wouter J Heerink
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
- Center for Medical Imaging, University of Groningen, Groningen, Netherlands
| | - Koert P de Jong
- Department of HPB Surgery and Liver Transplantation, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
- Center for Medical Imaging, University of Groningen, Groningen, Netherlands
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Liu D, Brace CL. Evaluation of tissue deformation during radiofrequency and microwave ablation procedures: Influence of output energy delivery. Med Phys 2019; 46:4127-4134. [PMID: 31260115 DOI: 10.1002/mp.13688] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 06/07/2019] [Accepted: 06/22/2019] [Indexed: 12/12/2022] Open
Abstract
PURPOSE The purpose of this study was to quantitatively analyze tissue deformation during radiofrequency (RF) and microwave ablation for varying output energy levels. METHODS A total of 46 fiducial markers which were classified into outer, middle, and inner lines were positioned into a single plane around an RF or microwave ablation applicator in each ex vivo bovine liver sample (8 cm × 6 cm × 4 cm, n = 18). Radiofrequency (500 kHz; ~35 W average) or microwave (2.4 GHz; 50-100 W output, ~35-70 W delivered) ablation was performed for 10 min (n = 4-6 each setting). CT images were acquired over the entire liver volume every 15 s. Principle strain magnitude and direction were determined from fiducial marker displacement. Normal and shear strain were then calculated such that negative strain denoted contraction and positive strain denoted expansion. Temporal variations, the final magnitudes, and angles of the strain were compared across energy delivery settings, using one-way ANOVA with post hoc Tukey's tests. RESULTS On average, tissue strain rates peak at around 1 min and decayed exponentially over time. No evidence of tissue expansion was observed. The tissue strains from RF and 50 W, 75 W, and 100 W microwave ablation at 10 min were -8.5%, -38.9%, -54.4%, and -65.7%, respectively, from the inner region and -3.6%, -23.7%, -41.8%, and -44.3%, respectively, from the outer region. Negative strain magnitude was positively correlated to energy delivery in the inner region (Spearman's ρ = -0.99). Microwaves at higher powers (75-100 W) induced significantly more strain than at lower power (50 W) or after RF ablation (P < 0.01). Principal strain angles ranged from 0.8° to -8.1°, indicating that tissue deformed more in the direction transverse to the applicator than along the direction of the applicator. CONCLUSIONS The influence of output energy on tissue deformation during RF and microwave ablation was analyzed. Microwave ablation created significantly greater contraction than RF ablation with similar energy delivery. During microwave ablation, more contraction was noted at higher power levels and in proximity to the antenna. Contraction primarily transverse to the antenna produces ablation zones that are more elongated than the original tissue volume.
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Affiliation(s)
- Dong Liu
- Departments of Radiology, Biomedical Engineering, University of Wisconsin, Madison, WI, 53705, USA
| | - Christopher L Brace
- Departments of Radiology, Biomedical Engineering, University of Wisconsin, Madison, WI, 53705, USA
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Strigari L, Minosse S, D'Alessio D, Farina L, Cavagnaro M, Cassano B, Pinto R, Vallati G, Lopresto V. Microwave thermal ablation using CT-scanner for predicting the variation of ablated region over time: advantages and limitations. Phys Med Biol 2019; 64:115021. [PMID: 30995620 DOI: 10.1088/1361-6560/ab1a67] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This study aims at investigating in real-time the structural and dynamical changes occurring in an ex vivo tissue during a microwave thermal ablation (MTA) procedure. The experimental set-up was based on ex vivo liver tissue inserted in a dedicated box, in which 3 fibre-optic (FO) temperature probes were introduced to measure the temperature increase over time. Computed tomography (CT) imaging technique was exploited to experimentally study in real-time the Hounsfield Units (HU) modification occurring during MTA. The collected image data were processed with a dedicated MATLAB tool, developed to analyse the FO positions and HU modifications from the CT images acquired over time before and during the ablation procedures. The radial position of a FO temperature probe (rFO) and the value of HU in the region of interest (ROI) containing the probe (HUo), along with the corresponding value of HU in the contralateral ROI with respect to the MTA antenna applicator (HUc), were determined and registered over time during and after the MTA procedure. Six experiments were conducted to confirm results. The correlation between temperature and the above listed predictors was investigated using univariate and multivariate analysis. At the multivariate analysis, the time, rFO and HUc resulted significant predictive factors of the logarithm of measured temperature. The correlation between predicted and measured temperatures was 0.934 (p < 0.001). The developed tool allows identifying and registering the image-based parameters useful for predicting the temperature variation over time in each investigated voxel by taking into consideration the HU variation.
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Affiliation(s)
- L Strigari
- Laboratory of Medical Physics and Expert Systems, IRCCS Regina Elena National Cancer Institute, IFO, via Elio Chianesi, 53, 00144, Rome, Italy. Current address: Department of Medical Physics, St. Orsola-Malpighi University Hospital, via Massarenti 9 40138 Bologna, Italy
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Lopresto V, Argentieri A, Pinto R, Cavagnaro M. Temperature dependence of thermal properties of ex vivo liver tissue up to ablative temperatures. ACTA ACUST UNITED AC 2019; 64:105016. [DOI: 10.1088/1361-6560/ab1663] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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26
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Hübner F, Schreiner R, Reimann C, Bazrafshan B, Kaltenbach B, Schüßler M, Jakoby R, Vogl TJ. Ex vivo validation of microwave thermal ablation simulation using different flow coefficients in the porcine liver. Med Eng Phys 2019; 66:56-64. [PMID: 30826254 DOI: 10.1016/j.medengphy.2019.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 02/06/2019] [Accepted: 02/11/2019] [Indexed: 12/25/2022]
Abstract
The purpose of the study was to validate the simulation model for a microwave thermal ablation in ex vivo liver tissue. The study aims to show that heat transfer due to the flow of tissue water during ablation in ex vivo tissue is not negligible. Ablation experiments were performed in ex vivo porcine liver with microwave powers of 60 W to 100 W. During the procedure, the temperature was recorded in the liver sample at different distances to the applicator using a fiber-optic thermometer. The position of the probes was identified by CT imaging and transferred to the simulation. The simulation of the heat distribution in the liver tissue was carried out with the software CST Studio Suite. The results of the simulation with different flow coefficients were compared with the results of the ablation experiments using the Bland-Altman analysis. The analysis showed that the flow coefficient of 90,000 W/(K*m3) can be considered as the most suitable value for clinically used powers. The presented simulation model can be used to calculate the temperature distribution for microwave ablation in ex vivo liver tissue.
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Affiliation(s)
- Frank Hübner
- Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe - University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
| | - Roland Schreiner
- Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe - University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Carolin Reimann
- Institute for Microwave Engineering and Photonics, Technische Universität Darmstadt, Merckstrasse 25, 64283 Darmstadt, Germany
| | - Babak Bazrafshan
- Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe - University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Benjamin Kaltenbach
- Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe - University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Martin Schüßler
- Institute for Microwave Engineering and Photonics, Technische Universität Darmstadt, Merckstrasse 25, 64283 Darmstadt, Germany
| | - Rolf Jakoby
- Institute for Microwave Engineering and Photonics, Technische Universität Darmstadt, Merckstrasse 25, 64283 Darmstadt, Germany
| | - Thomas Josef Vogl
- Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe - University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
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Solbiati M, Muglia R, Goldberg SN, Ierace T, Rotilio A, Passera KM, Marre I, Solbiati L. A novel software platform for volumetric assessment of ablation completeness. Int J Hyperthermia 2019; 36:337-343. [PMID: 30729818 DOI: 10.1080/02656736.2019.1569267] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
| | - Riccardo Muglia
- Department of Biomedical Sciences, Humanitas University, Rozzano, Milan, Italy
| | - S. Nahum Goldberg
- Department of Radiology, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Tiziana Ierace
- Department of Radiology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | | | | | | | - Luigi Solbiati
- Department of Biomedical Sciences, Humanitas University, Rozzano, Milan, Italy
- Department of Radiology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
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28
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Liu D, Adams MS, Burdette EC, Diederich CJ. Transurethral high-intensity ultrasound for treatment of stress urinary incontinence (SUI): simulation studies with patient-specific models. Int J Hyperthermia 2018; 34:1236-1247. [PMID: 29566562 PMCID: PMC6136964 DOI: 10.1080/02656736.2018.1456679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/16/2018] [Accepted: 03/17/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Stress urinary incontinence (SUI) is prevalent in adult women, attributed to weakened endopelvic supporting tissues, and typically treated using drugs and invasive surgical procedures. The objective of this in silico study is to explore transurethral high-intensity ultrasound for delivery of precise thermal therapy to the endopelvic tissues adjacent to the mid-urethra, to induce thermal remodeling as a potential minimally invasive treatment alternative. METHODS 3D acoustic (Rayleigh-Sommerfeld) and biothermal (Pennes bioheat) models of the ultrasound applicator and surrounding tissues were devised. Parametric studies over transducer configuration [frequency, radius-of-curvature (ROC)] and treatment settings (power, duration) were performed, and select cases on patient-specific models were used for further evaluation. Transient temperature and thermal dose distributions were calculated, and temperature and dose metrics reported. RESULTS Configurations using a 5-MHz curvilinear transducer (3.5 × 10 mm, 28 mm ROC) with single 90 s sonication can create heated zones with 11 mm penetration (>50 °C) while sparing the inner 1.8 mm (<45 °C) radial depth of the urethral mucosa. Sequential and discrete applicator rotations can sweep out bilateral coagulation volumes (1.4 W power, 15° rotations, 600 s total time), produce large volumetric (1124 mm³ above 60 EM43 °C) and wide angular (∼50.5° per lateral sweep) coverage, with up to 15.6 mm thermal penetration and at least 1.6 mm radial urethral protection (<5 EM43 °C). CONCLUSION Transurethral applicators with curvilinear ultrasound transducers can deliver spatially selective temperature elevations to lateral mid-urethral targets as a possible means to tighten the endopelvic fascia and adjacent tissues.
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Affiliation(s)
- Dong Liu
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | - Matthew S. Adams
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | | | - Chris J. Diederich
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
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29
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Wang Z, Tang X, Qi X, Shi Y, Chi J, Li P, Zhai B. Feasibility, safety, and efficacy of ultrasound-guided percutaneous microwave ablation for giant hepatic hemangioma. Int J Hyperthermia 2018; 35:246-252. [PMID: 30130992 DOI: 10.1080/02656736.2018.1493541] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Hepatic hemangioma is a common benign liver tumor. The majority of cases are asymptomatic and require no specific treatment. The aim of this study was to evaluate the feasibility, safety and efficacy of microwave ablation (MWA) for symptomatic or enlarging giant hepatic hemangioma (≥10 cm). METHODS From December 2013 to June 2016, 12 patients with giant hepatic hemangioma (≥10 cm) underwent ultrasound-guided percutaneous MWA, and ablation-related complications were observed. All patients were followed up with magnetic resonance or enhanced CT imaging at one month postoperatively to evaluate efficacy. RESULTS This study included a total of 13 giant hepatic hemangiomas (mean: 11.7 ± 1.6 cm) in 12 patients who initially underwent 16 sessions of MWA; three lesions were treated with two sessions of planned ablation. The average ablation time for a single hepatic hemangioma was 39.0 ± 14.4 minutes. Two patients had acute postoperative non-oliguric renal insufficiency without intra-abdominal hemorrhage, liver failure or other complications. Initially, complete ablation was achieved in ten lesions in nine patients (76.9%, 10/13). One patient underwent a second session of MWA at 5 months postoperatively due to fast growing residual tissue; complete necrosis was achieved after treatment. The remaining two cases did not receive any invasive treatment due to small residual volumes. The total complete ablation rate was 84.6% (11/13). CONCLUSION Image-guided MWA is a safe, feasible, effective treatment for giant hepatic hemangioma; these findings may open a new avenue for treatment.
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Affiliation(s)
- Zhi Wang
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Xiaoyin Tang
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Xingxing Qi
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Yaoping Shi
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Jiachang Chi
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Ping Li
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
| | - Bo Zhai
- a Department of Interventional Oncology , Renji Hospital, School of Medicine, Shanghai Jiaotong University , Shanghai , China
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30
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Lopresto V, Strigari L, Farina L, Minosse S, Pinto R, D’Alessio D, Cassano B, Cavagnaro M. CT-based investigation of the contraction ofex vivotissue undergoing microwave thermal ablation. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1361-6560/aaaf07] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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31
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Ziv O, Goldberg SN, Nissenbaum Y, Sosna J, Weiss N, Azhari H. Optical flow and image segmentation analysis for noninvasive precise mapping of microwave thermal ablation in X-ray CT scans - ex vivo study. Int J Hyperthermia 2017; 34:744-755. [PMID: 28866952 DOI: 10.1080/02656736.2017.1375160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To develop image processing algorithms for noninvasive mapping of microwave thermal ablation using X-ray CT. METHODS Ten specimens of bovine liver were subjected to microwave ablation (20-80 W, 8 min) while scanned by X-ray CT at 5 s intervals. Specimens were cut and manually traced by two observers. Two algorithms were developed and implemented to map the ablation zone. The first algorithm utilises images segmentation of Hounsfield units changes (ISHU). The second algorithm utilises radial optical flow (ROF). Algorithm sensitivity to spatiotemporal under-sampling was assessed by decreasing the acquisition rate and reducing the number of acquired projections used for image reconstruction in order to evaluate the feasibility of implementing radiation reduction techniques. RESULTS The average radial discrepancy between the ISHU and ROF contours and the manual tracing were 1.04±0.74 and 1.16±0.79mm, respectively. When diluting the input data, the ISHU algorithm retained its accuracy, ranging from 1.04 to 1.79mm. By contrast, the ROF algorithm performance became inconsistent at low acquisition rates. Both algorithms were not sensitive to projections reduction, (ISHU: 1.24±0.83mm, ROF: 1.53±1.15mm, for reduction by eight fold). Ablations near large blood vessels affected the ROF algorithm performance (1.83±1.30mm; p < 0.01), whereas ISHU performance remained the same. CONCLUSION The two suggested noninvasive ablation mapping algorithms can provide highly accurate contouring of the ablation zone at low scan rates. The ISHU algorithm may be more suitable for clinical practice as it appears more robust when radiation dose reduction strategies are employed and when the ablation zone is near large blood vessels.
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Affiliation(s)
- Omri Ziv
- a Department of Biomedical Engineering , Technion - IIT , Haifa , Israel
| | - S Nahum Goldberg
- b Department of Radiology , Hadassah Medical Center, Hebrew University , Jerusalem , Israel.,c Department of Radiology , Beth Israel Deaconess Medical Center , Boston , MA , USA
| | - Yitzhak Nissenbaum
- b Department of Radiology , Hadassah Medical Center, Hebrew University , Jerusalem , Israel
| | - Jacob Sosna
- b Department of Radiology , Hadassah Medical Center, Hebrew University , Jerusalem , Israel.,c Department of Radiology , Beth Israel Deaconess Medical Center , Boston , MA , USA
| | - Noam Weiss
- a Department of Biomedical Engineering , Technion - IIT , Haifa , Israel
| | - Haim Azhari
- a Department of Biomedical Engineering , Technion - IIT , Haifa , Israel
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32
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Farina L, Nissenbaum Y, Cavagnaro M, Goldberg SN. Tissue shrinkage in microwave thermal ablation: comparison of three commercial devices. Int J Hyperthermia 2017; 34:382-391. [DOI: 10.1080/02656736.2017.1362115] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Laura Farina
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy
| | - Yitzhak Nissenbaum
- Department of Radiology, Hadassah Hebrew University, Medical Center, Jerusalem, Israel
| | - Marta Cavagnaro
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy
| | - S. Nahum Goldberg
- Department of Radiology, Hadassah Hebrew University, Medical Center, Jerusalem, Israel
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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33
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Deshazer G, Hagmann M, Merck D, Sebek J, Moore KB, Prakash P. Computational modeling of 915 MHz microwave ablation: Comparative assessment of temperature-dependent tissue dielectric models. Med Phys 2017; 44:4859-4868. [DOI: 10.1002/mp.12359] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 04/20/2017] [Accepted: 04/20/2017] [Indexed: 12/28/2022] Open
Affiliation(s)
- Garron Deshazer
- Department of Radiation Oncology; Siteman Cancer Center; Barnes-Jewish Hospital & Washington University School of Medicine; 4921 Parkview Pl St. Louis MO 63110 USA
- Department of Diagnostic Imaging; Rhode Island Hospital; 593 Eddy Street Providence RI 02903 USA
| | - Mark Hagmann
- Perseon Medical; 2188 W 2200 S Salt Lake City UT 84119 USA
| | - Derek Merck
- Department of Diagnostic Imaging; Rhode Island Hospital; 593 Eddy Street Providence RI 02903 USA
| | - Jan Sebek
- Department of Electrical and Computer Engineering; Kansas State University; Manhattan KS 66506 USA
| | - Kent B. Moore
- Perseon Medical; 2188 W 2200 S Salt Lake City UT 84119 USA
| | - Punit Prakash
- Department of Electrical and Computer Engineering; Kansas State University; Manhattan KS 66506 USA
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34
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Lopresto V, Pinto R, Farina L, Cavagnaro M. Microwave thermal ablation: Effects of tissue properties variations on predictive models for treatment planning. Med Eng Phys 2017. [PMID: 28647287 DOI: 10.1016/j.medengphy.2017.06.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Microwave thermal ablation (MTA) therapy for cancer treatments relies on the absorption of electromagnetic energy at microwave frequencies to induce a very high and localized temperature increase, which causes an irreversible thermal damage in the target zone. Treatment planning in MTA is based on experimental observations of ablation zones in ex vivo tissue, while predicting the treatment outcomes could be greatly improved by reliable numerical models. In this work, a fully dynamical simulation model is exploited to look at effects of temperature-dependent variations in the dielectric and thermal properties of the targeted tissue on the prediction of the temperature increase and the extension of the thermally coagulated zone. In particular, the influence of measurement uncertainty of tissue parameters on the numerical results is investigated. Numerical data were compared with data from MTA experiments performed on ex vivo bovine liver tissue at 2.45GHz, with a power of 60W applied for 10min. By including in the simulation model an uncertainty budget (CI=95%) of ±25% in the properties of the tissue due to inaccuracy of measurements, numerical results were achieved in the range of experimental data. Obtained results also showed that the specific heat especially influences the extension of the thermally coagulated zone, with an increase of 27% in length and 7% in diameter when a variation of -25% is considered with respect to the value of the reference simulation model.
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Affiliation(s)
- Vanni Lopresto
- ENEA, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy.
| | - Rosanna Pinto
- ENEA, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
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35
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Park CS, Liu C, Hall SK, Payne SJ. A thermoelastic deformation model of tissue contraction during thermal ablation. Int J Hyperthermia 2017; 34:221-228. [DOI: 10.1080/02656736.2017.1335441] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Chang Sub Park
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Cong Liu
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Sheldon K. Hall
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stephen J. Payne
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
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36
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De Cobelli F, Marra P, Ratti F, Ambrosi A, Colombo M, Damascelli A, Sallemi C, Gusmini S, Salvioni M, Diana P, Cipriani F, Venturini M, Aldrighetti L, Del Maschio A. Microwave ablation of liver malignancies: comparison of effects and early outcomes of percutaneous and intraoperative approaches with different liver conditions : New advances in interventional oncology: state of the art. Med Oncol 2017; 34:49. [PMID: 28220346 DOI: 10.1007/s12032-017-0903-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/12/2017] [Indexed: 12/13/2022]
Abstract
Liver thermal ablation is an alternative treatment for hepatocellular carcinoma (HCC) and secondary liver malignancies. Microwave ablation (MWA) produces large ablation zones (AZ) in short time; however, AZ prediction is based on preclinical ex vivo models, rising concerns about reproducibility and safety in humans. We aimed to investigate the effects produced by a new-generation MWA system on human liver in vivo with different approaches (percutaneous or intraoperative) and liver conditions (cirrhosis or previous chemotherapy treatment), in comparison with manufacturer-provided predictions based on ex vivo animal models. Complete tumor ablation (CA) and early clinical outcomes were also assessed. From October 2014, 60 consecutive patients (cirrhotic = 31; non-cirrhotic = 10; chemotherapy-treated = 19) with 81 liver nodules (HCC = 31; mets = 50) underwent MWA procedures (percutaneous = 30; laparotomic = 18; laparoscopic = 12), with a 2450 MHz/100 W generator with Thermosphere™ Technology (Emprint™, Medtronic). A contrast-enhanced CT or MR was performed after one month to assess CA and measure AZ. A linear correlation between AZ volumes and ablation times was observed in vivo, without differences from manufacturer-provided ex vivo predictions in all operative approaches and liver conditions. Other independent variables (sex, age, nodule location) showed no relationship when added to the model. Median (IQR) longitudinal and transverse roundness-indexes of the AZs were, respectively, 0.77(0.13) and 0.93(0.11). CA at 1 month was 93% for percutaneous and 100% for intraoperative procedures (p = 0.175). Thirty-day morbidity and mortality were 3% and 0%. MWA with Thermosphere™ Technology produces predictable AZs on human liver in vivo, according to manufacturer-provided ex vivo predictions. In our experience, this new-generation MWA system is effective and safe to treat liver malignancies in different operative and clinical settings.
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Affiliation(s)
- Francesco De Cobelli
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Paolo Marra
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy. .,Vita-Salute San Raffaele University, Milan, Italy.
| | - Francesca Ratti
- Department of Surgery, Hepato-biliary Surgery Unit, San Raffaele Scientific Institute, Milan, Italy
| | | | - Michele Colombo
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Anna Damascelli
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Claudio Sallemi
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy
| | - Simone Gusmini
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy
| | - Marco Salvioni
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy
| | - Pietro Diana
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Federica Cipriani
- Department of Surgery, Hepato-biliary Surgery Unit, San Raffaele Scientific Institute, Milan, Italy
| | - Massimo Venturini
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Luca Aldrighetti
- Department of Surgery, Hepato-biliary Surgery Unit, San Raffaele Scientific Institute, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Alessandro Del Maschio
- Department of Radiology and Experimental Imaging Center, San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
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37
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Liu D, Brace CL. Numerical simulation of microwave ablation incorporating tissue contraction based on thermal dose. Phys Med Biol 2017; 62:2070-2086. [PMID: 28151729 DOI: 10.1088/1361-6560/aa5de4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Tissue contraction plays an important role during high temperature tumor ablation, particularly during device characterization, treatment planning and imaging follow up. We measured such contraction in 18 ex vivo bovine liver samples during microwave ablation by tracking fiducial motion on CT imaging. Contraction was then described using a thermal dose dependent model and a negative thermal expansion coefficient based on the empirical data. FEM simulations with integrated electromagnetic wave propagation, heat transfer, and structural mechanics were evaluated using temperature-dependent dielectric properties and the negative thermal expansion models. Simulated temperature and displacement curves were then compared with the ex vivo experimental results on different continuous output powers. The optimized thermal dose model indicated over 50% volumetric contraction occurred at the temperature over 102.1 °C. The numerical simulation results on temperature and contraction-induced displacement showed a good agreement with experimental results. At microwave powers of 55 W, the mean errors on temperature between simulation and experimental results were 8.25%, 2.19% and 5.67% at 5 mm, 10 mm and 20 mm radially from the antenna, respectively. The simulated displacements had mean errors of 16.60%, 14.08% and 23.45% at the same radial locations. Compared to the experimental results, the simulations at the other microwave powers had larger errors with 10-40% mean errors at 40 W, and 10-30% mean errors at 25 W. The proposed model is able to predict temperature elevation and simulate tissue deformation during microwave ablation, and therefore may be incorporated into treatment planning and clinical translation from numerical simulations.
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Affiliation(s)
- Dong Liu
- Department of Radiology and Biomedical Engineering, University of Wisconsin-Madison, 1111 Highland Ave, Madison WI 53705, United States of America
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38
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Cornelis FH, Marcelin C, Bernhard JC. Microwave ablation of renal tumors: A narrative review of technical considerations and clinical results. Diagn Interv Imaging 2016; 98:287-297. [PMID: 28011104 DOI: 10.1016/j.diii.2016.12.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 12/01/2016] [Indexed: 12/22/2022]
Abstract
PURPOSE The purpose of this review was to identify the specific technical considerations to adequately perform microwave ablations (MWA) of renal tumors and analyze the currently available clinical results. METHODS Using Medline, a systematic review was performed including articles published between January 2000 and September 2016. English language original articles, reviews and editorials were selected based on their clinical relevance. RESULTS MWA has several theoretical advantages over radiofrequency ablation in consistently providing higher intratumoral temperatures. MWA is less dependent of electrical conductivities of tissues and the delivered energy is less limited by desiccation of heated tissues. While there are insufficient data, especially because of a lack of studies with mid- to long-term follow-up, to determine the oncologic effectiveness of MWA, this technique appears safe and effective for the ablation of T1 renal tumors. There is evidence for using mid-level settings based on experimental and clinical data. Power set at 50-65W for 5-15min appears adequate in kidney but close clinical and imaging follow-up have to be performed. CONCLUSION Renal MWA offers theoretical advantages by comparison with other available techniques to treat renal tumors. However, MWA suffers of less cumulative data compared to radiofrequency ablation or cryoablation. Moreover, microwaves still require further studies to identify the optimal tumor characteristics and device settings leading to predictable ablation.
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Affiliation(s)
- F H Cornelis
- Department of radiology, Tenon hospital, 4, rue de la Chine, 75020 Paris, France.
| | - C Marcelin
- Department of radiology, Pellegrin hospital, place Amélie-Raba-Léon, 33076 Bordeaux, France
| | - J-C Bernhard
- Department of urology, Pellegrin hospital, place Amélie-Raba-Léon, 33076 Bordeaux, France
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39
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Lopresto V, Pinto R, Farina L, Cavagnaro M. Treatment planning in microwave thermal ablation: clinical gaps and recent research advances. Int J Hyperthermia 2016; 33:83-100. [PMID: 27431328 DOI: 10.1080/02656736.2016.1214883] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Microwave thermal ablation (MTA) is a minimally invasive therapeutic technique aimed at destroying pathologic tissues through a very high temperature increase induced by the absorption of an electromagnetic field at microwave (MW) frequencies. Open problems, which are delaying MTA applications in clinical practice, are mainly linked to the extremely high temperatures, up to 120 °C, reached by the tissue close to the antenna applicator, as well as to the ability of foreseeing and controlling the shape and dimension of the thermally ablated area. Recent research was devoted to the characterisation of dielectric, thermal and physical properties of tissue looking at their changes with the increasing temperature, looking for possible developments of reliable, automatic and personalised treatment planning. In this paper, a review of the recently obtained results as well as new unpublished data will be presented and discussed.
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Affiliation(s)
- V Lopresto
- a Division of Health Protection Technologies , Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) , Rome , Italy
| | - R Pinto
- a Division of Health Protection Technologies , Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) , Rome , Italy
| | - L Farina
- b Department of Information Engineering, Electronics and Telecommunications , Sapienza University of Rome , Rome , Italy
| | - M Cavagnaro
- b Department of Information Engineering, Electronics and Telecommunications , Sapienza University of Rome , Rome , Italy
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40
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Park CS, Hall SK, Liu C, Payne SJ. A model of tissue contraction during thermal ablation. Physiol Meas 2016; 37:1474-84. [DOI: 10.1088/0967-3334/37/9/1474] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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Meloni MF, Chiang J, Laeseke PF, Dietrich CF, Sannino A, Solbiati M, Nocerino E, Brace CL, Lee FT. Microwave ablation in primary and secondary liver tumours: technical and clinical approaches. Int J Hyperthermia 2016; 33:15-24. [PMID: 27416729 DOI: 10.1080/02656736.2016.1209694] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Thermal ablation is increasingly being utilised in the treatment of primary and metastatic liver tumours, both as curative therapy and as a bridge to transplantation. Recent advances in high-powered microwave ablation systems have allowed physicians to realise the theoretical heating advantages of microwave energy compared to other ablation modalities. As a result there is a growing body of literature detailing the effects of microwave energy on tissue heating, as well as its effect on clinical outcomes. This article will discuss the relevant physics, review current clinical outcomes and then describe the current techniques used to optimise patient care when using microwave ablation systems.
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Affiliation(s)
- Maria Franca Meloni
- a Department of Radiology , Interventional Ultrasound, Institute of Care IGEA , Milan , Italy
| | - Jason Chiang
- b Department of Radiology , University of Wisconsin , Madison , Wisconsin , USA
| | - Paul F Laeseke
- b Department of Radiology , University of Wisconsin , Madison , Wisconsin , USA
| | - Christoph F Dietrich
- c Department of Internal Medicine , Caritas Krankenhas Bad Mergentheim , Bad Mergentheim , Germany
| | - Angela Sannino
- d Department of Clinical Medicine and Surgery , University of Naples Federico II , Naples , Italy
| | - Marco Solbiati
- e Department of Electronics, Information and Bioengineering , Politecnico Milano , Milan , Italy
| | - Elisabetta Nocerino
- f Department of Radiology , San Paolo Hospital, University of Milan , Milan , Italy
| | - Christopher L Brace
- b Department of Radiology , University of Wisconsin , Madison , Wisconsin , USA
| | - Fred T Lee
- b Department of Radiology , University of Wisconsin , Madison , Wisconsin , USA
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Amabile C, Ahmed M, Solbiati L, Meloni MF, Solbiati M, Cassarino S, Tosoratti N, Nissenbaum Y, Ierace T, Goldberg SN. Microwave ablation of primary and secondary liver tumours: ex vivo, in vivo, and clinical characterisation. Int J Hyperthermia 2016; 33:34-42. [PMID: 27443519 DOI: 10.1080/02656736.2016.1196830] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
| | - Muneeb Ahmed
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Luigi Solbiati
- Department of Interventional Oncologic Radiology, General Hospital of Busto Arsizio, Busto Arsizio, Italy
| | | | - Marco Solbiati
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | | | | | - Yitzhak Nissenbaum
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - Tiziana Ierace
- Department of Interventional Oncologic Radiology, General Hospital of Busto Arsizio, Busto Arsizio, Italy
| | - S. Nahum Goldberg
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
- Department of Radiology, Hadassah Hebrew University Medical Centre, Jerusalem, Israel
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Amabile C, Farina L, Lopresto V, Pinto R, Cassarino S, Tosoratti N, Goldberg SN, Cavagnaro M. Tissue shrinkage in microwave ablation of liver: an ex vivo predictive model. Int J Hyperthermia 2016; 33:101-109. [DOI: 10.1080/02656736.2016.1208292] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
| | - Laura Farina
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome
| | - Vanni Lopresto
- Division of Health Protection Technologies, Casaccia Research Centre, Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Rome, Italy
| | - Rosanna Pinto
- Division of Health Protection Technologies, Casaccia Research Centre, Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Rome, Italy
| | | | | | - S. Nahum Goldberg
- Department of Radiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel, and Department of Radiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Marta Cavagnaro
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome
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Freedman J, Nilsson H, Jonas E. New horizons in ablation therapy for hepatocellular carcinoma. Hepat Oncol 2015; 2:349-358. [PMID: 30191017 DOI: 10.2217/hep.15.28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Historically ablative treatment for hepatocellular cancer (HCC) has been regarded as inferior to transplantation and resection and has therefore been reserved for patients not suitable for surgical intervention in stage 0-A HCC according to the Barcelona Clinic Liver Cancer classification system. In the wake of surgical strategies challenging the current Barcelona Clinic Liver Cancer treatment guidelines and improvements in imaging, targeting and ablation technologies, ablation is likely to occupy a more central role in the management of patients with HCC, challenging its historically perceived inferiority to resection.
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Affiliation(s)
- Jacob Freedman
- Karolinska Institutet, Department of Clinical Sciences, Division of Surgery, Danderyd Hospital, 182 88 Stockholm, Sweden.,Karolinska Institutet, Department of Clinical Sciences, Division of Surgery, Danderyd Hospital, 182 88 Stockholm, Sweden
| | - Henrik Nilsson
- Karolinska Institutet, Department of Clinical Sciences, Division of Surgery, Danderyd Hospital, 182 88 Stockholm, Sweden.,Karolinska Institutet, Department of Clinical Sciences, Division of Surgery, Danderyd Hospital, 182 88 Stockholm, Sweden
| | - Eduard Jonas
- Clintec, Karolinska Institute, Department of Surgery, Karolinska University Hospital, Stockholm, Sweden.,Clintec, Karolinska Institute, Department of Surgery, Karolinska University Hospital, Stockholm, Sweden
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