Monitoring Microwave Ablation Treatments for Liver Tumors Using Ultrasound Elastography PDF Download

Author: Wenjun Yang
Publisher:
ISBN:
Category :
Languages : en
Pages : 264

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Book Description
Liver cancer is the sixth most common and the third leading cause of cancer related deaths world-wide. New cases and mortality in the U.S. have doubled during the past two decades, increasing at a rate of 3.4% per year from 2007 to 2011. Existing treatment methods for liver cancer include partial hepatectomy, embolization with chemotherapy, liver transplant, and percutaneous ablation. Percutaneous ablation is increasingly being adopted as an effective treatment method for liver cancer by thermal necrosis of cancerous tissue, with the advantage of promising treatment outcomes, and minimally invasive procedures. Previously percutaneous ablation was performed using radiofrequency ablation (RFA), which uses a local circuit loop to generate a thermal dose. To improve the heating rate and volume treated with RFA, microwave ablation (MWA) was introduced which heated local tissue by agitating water molecules using microwave energy. The key factor to yield a promising treatment outcome with MWA is to effectively monitor the ablation margin of the treated region. The guidance imaging modality for MWA, namely ultrasound B-mode imaging is not sufficient to delineate the ablated region after the MWA procedure. Thus, computed tomography (CT) is adopted as the current gold standard to determine the ablation margin by comparing the pre- and post- treatment images. However, CT scans prolong the treatment time and expose the patients to ionizing radiation. In this dissertation, an ultrasound elastography technique, which is referred to as electrode displacement elastography (EDE), is applied for monitoring clinical MWA procedures. By comparison with B-mode imaging and commercial acoustic radiation force impulse imaging (ARFI), EDE is potentially an alternative imaging modality to provide effective real-time feedback of the ablated margin, which might improve treatment outcomes with MWA. In addition, our previously introduced three-dimensional (3D) reconstruction algorithm, Sheaf of Ultrasound Planes Reconstruction (SOUPR) was applied for a phantom study to depict the ablation inclusion as a 3D volume instead of a single 2D ultrasound plane. An image fusion technique is also developed to register EDE and CT to determine the ablation margin on EDE with comparison to the current gold standard.

Author: Ping Liang
Publisher: Springer
ISBN: 9401793158
Category : Medical
Languages : en
Pages : 333

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Book Description
Microwave ablation is a simple, affordable, and highly precise technique. After its successful application in treating liver tumors, it is now widely used to combat renal tumors, adrenal tumors, thyroid nodes, uterine fibroids and other solid tumors. This book presents 40 successful cases of treating these diseases. A series of picture before treatment, after treatment and from different angles is provided for each kind of tumor treatment. In each chapter, step by step operative techniques and illustrations are included. This book also examines CT, NMR and ultrasonography to evaluate the effect of microwave ablation. Editor Ping Liang, is the Director and Professor at Dept. of Interventional Ultrasound, General Hospital of PLA, Beijing, China. Editor Xiaoling Yu is Professor and Chief physician, Editor Jie Yu is Associate Chief physician at the same department.

Author: Swetha Subramanian
Publisher:
ISBN:
Category :
Languages : en
Pages : 145

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Book Description
Hepatocellular carcinoma (HCC) and colorectal metastases (CRC) are common tumors worldwide with an increasing incidence in the United States. Thermal ablation techniques such as radiofrequency ablation (RFA), high intensity focused ultrasound (HIFU), microwave and laser ablation techniques have shown potential to treat unresectable tumors. Still lacking is a treatment monitoring technique that can accurately predict ablation. Echo decorrelation imaging is a novel pulse-echo ultrasound imaging method that quantifies and maps changes in echo signals occurring over millisecond time scales during thermal ablation. In this dissertation, the utility of echo decorrelation imaging as a treatment monitoring tool was assessed during in vivo and in vitro thermal ablation. To test the utility of echo decorrelation imaging for the prediction of ablation, RFA was performed on ex vivo bovine liver ( N = 9). Echo decorrelation was computed from the Hilbert transformed pulse-echo data acquired during RFA treatments. For comparison, integrated backscatter was also computed from the same data. Pixel-by-pixel comparison between the echo decorrelation and integrated backscatter maps and the ablated region from gross tissue histology was performed using receiver operating characteristic (ROC) curves. Echo decorrelation and integrated backscatter were then quantitatively evaluated as predictors of ablation. The area under the ROC curves (AUROC) was determined for both echo decorrelation and integrated backscatter imaging methods. Ablation was predicted more accurately with echo decorrelation (AUROC = 0.820) than with integrated backscatter (AUROC = 0.668). To test the utility of echo decorrelation imaging for the prediction of ablation during in vivo thermal ablation, RFA was performed on normal swine liver ( N = 5) and ultrasound ablation using image-ablate arrays was performed on rabbit liver implanted with VX2 tumors ( N = 2). Consistent with the in vitro studies, ablation was predicted more accurately with echo decorrelation (AUROC = 0.833 and 0.776 for RFA and ultrasound ablation, respectively) than with integrated backscatter (AUROC = 0.733 and 0.494). Mean cumulative echo decorrelation was greater in the ablated tissue regions compared to the unablated regions for both in vitro ( t = 6.808, p = 6.10-6, N = 9) and in vivo ( t = 3.498, p = 0.036, N = 5) RFA treatments, indicating the ability of echo decorrelation to delineate between the ablated and unablated regions. For in vivo RFA, motion gating reduced the mean echo decorrelation in both ablated ( t = 3.526, p = 0.036, N = 5) and unablated ( t = 5.173, p = 0.013, N = 5) regions. However, with or without motion gating, the mean cumulative echo decorrelation was significantly greater in the ablated region than in the unablated region ( t = 3.883, p = 0.008, N = 5). The effect of tissue temperature on echo decorrelation was assessed during in vitro RFA. RFA experiments ( N = 15) were performed on ex vivo bovine liver tissue. Temperature maps were simulated by a finite element method, with tissue parameters determined using an unscented Kalman filter to best match measured ablation results. Significantly higher AUROC values ( p = 0.019, p = 10-14, p = 10-14) were obtained for the prediction of tissue temperatures greater than 40, 60, and 80° C with echo decorrelation (AUROC = 0.871, 0.948, and 0.966) when compared to integrated backscatter (AUROC = 0.865, 0.877, and 0.832). Overall, the results presented in this dissertation show potential for the utility of echo decorrelation imaging as a treatment monitoring tool.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
Hepatocellular carcinoma is one of the leading causes of cancer related deaths worldwide. Percutaneous needle-based tumor ablation is a minimally invasive treatment method for liver tumors in patients that are not candidates for surgery. In order to prevent recurrence, it is crucial that the right volume of tissue and a safety margin around the tumor are completely ablated during treatment. Although magnetic resonance imaging and computed X-ray tomography are currently used for monitoring the procedure, ultrasound imaging is potentially safer and more cost-effective and can also provide real-time high frame rate imaging capabilities. Information about tissue stiffness obtained using ultrasound elastography can play an important role in locating the boundary of ablated tissue and help in planning and execution of the ablation procedure. The goal of this dissertation is to develop robust signal processing algorithms to delineate ablation boundaries based on stiffness variations estimated from high frame rate radiofrequency ultrasound echo data. Shear wave velocity is used as a surrogate for tissue stiffness. A method called electrode vibration elastography is used where the ablation needle is vibrated using an actuator and acts as a line source for shear waves. The shear wave pulse is tracked in the imaging plane as it travels laterally away from this line source. Model based denoising algorithms are developed to track the shear wave pulse and reconstruct two dimensional (2D) shear wave velocity images. In order to generate three dimensional (3D) visualizations of the ablated volume from 2D imaging planes, multiple 2D imaging slices are acquired in a sheaf geometry, with the ablation needle coinciding with the axis of the sheaf. Shear wave velocity information from the individual 2D imaging planes can be used to reconstruct transverse or C-planes that are stacked to generate a 3D visualization. The reconstruction is performed using a penalized least-squares algorithm. A computationally tractable iterative reconstruction algorithm that can handle 3D grids with millions of points is also developed.

Author: Eric van Sonnenberg
Publisher: Springer Science & Business Media
ISBN: 0387286748
Category : Medical
Languages : en
Pages : 554

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Book Description
There is an enormous sense of excitement in the communities of cancer research and cancer care as we move into the middle third of the ?rst decade of the 21st century. For the ?rst time,there is a true sense of c- ?dence that the tools provided by the human genome project will enable cancer researchers to crack the code of genomic abnormalities that allow tumor cells to live within the body and provide highly speci?c, virtually non-toxic therapies for the eradication,or at least ?rm control of human cancers. There is also good reason to hope that these same lines of inquiry will yield better tests for screening, early detection, and prev- tion of progression beyond curability. While these developments provide a legitimate basis for much op- mism, many patients will continue to develop cancers and suffer from their debilitating effects, even as research moves ahead. For these in- viduals, it is imperative that the cancer ?eld make the best possible use of the tools available to provide present day cancer patients with the best chances for cure, effective palliation, or, at the very least, relief from symptoms caused by acute intercurrent complications of cancer. A modality that has emerged as a very useful approach to at least some of these goals is tumor ablation by the use of physical or physiochemical approaches.

Author: Boris Rubinsky
Publisher: Springer Science & Business Media
ISBN: 364205420X
Category : Technology & Engineering
Languages : en
Pages : 320

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Book Description
Non-thermal irreversible electroporation is a new minimally invasive surgical p- cedure with unique molecular selectivity attributes – in fact it may be considered the first clinical molecular surgery procedure. Non-thermal irreversible electro- ration is a molecular selective mode of cell ablation that employs brief electrical fields to produce nanoscale defects in the cell membrane, which can lead to cell death, without an effect on any of the other tissue molecules. The electrical fields can be produced through contact by insertion of electrode needles around the undesirable tissue and non-invasively by electromagnetic induction. This new - dition to the medical armamentarium requires the active involvement and is of interest to clinical physicians, medical researchers, mechanical engineers, che- cal engineers, electrical engineers, instrumentation designers, medical companies and many other fields and disciplines that were never exposed in their training to irreversible electroporation or to a similar concept. This edited book is designed to be a comprehensive introduction to the field of irreversible electroporation to those that were not exposed or trained in the field before and can also serve as a reference manual. Irreversible electroporation is broad and interdisciplinary. Therefore, we have made an attempt to cover every one of the various aspects of the field from an introductory basic level to state of the art.

Author: Vincenzo Piemonte
Publisher: John Wiley & Sons
ISBN: 1119296048
Category : Science
Languages : en
Pages : 273

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Book Description
An important resource that puts the focus on the chemical engineering aspects of biomedical engineering In the past 50 years remarkable achievements have been advanced in the fields of biomedical and chemical engineering. With contributions from leading chemical engineers, Biomedical Engineering Challenges reviews the recent research and discovery that sits at the interface of engineering and biology. The authors explore the principles and practices that are applied to the ever-expanding array of such new areas as gene-therapy delivery, biosensor design, and the development of improved therapeutic compounds, imaging agents, and drug delivery vehicles. Filled with illustrative case studies, this important resource examines such important work as methods of growing human cells and tissues outside the body in order to repair or replace damaged tissues. In addition, the text covers a range of topics including the challenges faced with developing artificial lungs, kidneys, and livers; advances in 3D cell culture systems; and chemical reaction methodologies for biomedical imagining analysis. This vital resource: Covers interdisciplinary research at the interface between chemical engineering, biology, and chemistry Provides a series of valuable case studies describing current themes in biomedical engineering Explores chemical engineering principles such as mass transfer, bioreactor technologies as applied to problems such as cell culture, tissue engineering, and biomedical imaging Written from the point of view of chemical engineers, this authoritative guide offers a broad-ranging but concise overview of research at the interface of chemical engineering and biology.

Author: S. Kaisar Alam
Publisher: Elsevier
ISBN: 0128096845
Category : Science
Languages : en
Pages : 256

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Book Description
Tissue Elasticity Imaging: Volume Two: Clinical Applications offers an extensive treatment of the fundamentals and applications of this groundbreaking diagnostic modality. Techniques and results are presented for the assessment of breast, prostate, heart, liver and thyroid tissues. For each application, details are provided on how to perform each technique, along with methods of interpretation, diagnostic criteria, quality assurance, challenges and case studies. This book is an essential resource for all researchers and practitioners (including scientists, radiologists, urologists, fellows and residents) interested in any elasticity imaging modality. As many diseases, including cancers, alter tissue mechanical properties, it is not always possible for conventional methods to detect changes, but with elasticity images that are produced by slow tissue deformation or low-frequency vibration, these changes can be displayed. Offers the first comprehensive reference on elasticity imaging Discusses the fundamentals of technology and their limitations and solutions, along with advanced methods and future directions Addresses the technologies and applications useful to both researchers and clinical practitioners Includes an online reference section regularly updated with advances in technology and applications

Author: Mauro Monteiro Correia
Publisher: Springer Nature
ISBN: 3030254860
Category : Medical
Languages : en
Pages : 597

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Book Description
Colorectal cancer is the third most commonly diagnosed condition in oncology, affecting around 1.23 million individuals per year, according to recent statistics. Of these patients, about 50% will develop liver metastases and approximately 20% will present a stage IV disease at diagnosis. These statistics make colorectal liver metastases (CLM) an issue of major importance in current oncology. The area of CLM is subject to great and continuous advances, as its pathophysiologic mechanisms are better understood and more therapeutic and surgical options are developed. Consequently, all professionals involved with the diagnosis, treatment and follow up of CLM should be kept up to date with the latest advances on the field, to provide high standard medical care to their patients. This book is designed to present the state-of-the-art in CLM management and, in doing so, to review the current evidence on CLM, discussing all important topics in the field. Coverage is broad and comprehensive, encompassing introductory topics (history, definitions, epidemiology, etc.), basic science subjects (molecular biology, genetics, dissemination process, etc.) and practical clinical topics (tumor behavior, diagnosis, drug therapy, radiation therapy, surgery, ablation, multidisciplinary teams, etc.). Although comprehensive on the coverage and selection of topics, each chapter is concise and objective, dissecting topics in a practical and direct format. Evidences and recommendations are included. Chapters display a brief introduction of the common knowledge, go straight to the detailed revision of the most recent years of the literature, and end with practical closing observations. This book is a tool for professionals (general and cancer surgeons, HPB surgeons, clinical oncologists, gastroenterologists and medical residents) and interns who search for a qualified and reader friendly revision on topics concerning Colorectal Cancer Liver Metastases.

Author: Devashish Shrivastava
Publisher: John Wiley & Sons
ISBN: 1119799619
Category : Medical
Languages : en
Pages : 581

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Book Description
THE APPLICATION OF HEAT IN ONCOLOGY Understand the use of heat to destroy tumors with this comprehensive guide Heat is an indispensable resource in the destruction of cancerous tumors to potentially treat cancers. There are also real challenges, however, involved in the total destruction of tumors without destroying healthy tissue surrounding the tumor in the process. A detailed understanding of the propagation of thermal energy, induced heating, and tissue responses to heat is required to safely and successfully apply heat-based technologies in clinical oncology. The Application of Heat in Oncology supplies this understanding, with a thorough, comprehensive overview of the principle and practice involved. Offering both a detailed introduction to the physics and thermodynamics of induced heat and an analysis of its clinical applications, this is an essential resource for clinicians, technicians, and others in oncological practice. The Application of Heat in Oncology readers will also find: Guidelines for applying heat both safely and effectively Detailed discussion of topics including energy delivery (e.g., via RF, MW, ultrasound, laser, cryoagents, hyperthermia, nanoparticles, etc.), temperature assessment, damage assessment, image guidance, and more Summary of current practice along with suggestions for future areas of technological improvement The Application of Heat in Oncology is ideal for all clinicians working in the field of cancer treatment, including medical students, residents, researchers, engineers, radiologists, surgeons, and more.