Download or read book A New Modality for High Resolution Diffuse Optical Imaging written by Tiffany C. Kwong and published by . This book was released on 2017 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: As one of the most sensitive in vivo molecular imaging modalities, fluorescence imaging has great potential to play an important role in preclinical and clinical studies. Indeed, in vivo fluorescence optical imaging extends across a wide range of applications, from cellular to organ levels. Unfortunately, in organ level applications, fluorescence imaging suffers from low spatial resolution due to the high scattering nature of biological tissue, especially in deep tissue (>1cm). Extensive effort has been spent to improve the spatial resolution of fluorescence tomography (FT). However, approaches such as integrating FT with other anatomic imaging modalities such as Magnetic Resonance Imaging (MRI) or computed tomography (CT) do not perform well if the fluorescent agent distribution within the medium cannot be defined in the anatomical image. There are also several techniques that attempt to modulate fluorescence signals using ultrasound to achieve higher spatial resolution. However, low modulation efficiency and extremely low signal to noise ratio (SNR) are the two primary factors that make the implementation of these techniques difficult.Consequently, the poor spatial resolution and subsequent low quantitative accuracy are the main obstacles preventing the widespread use of this powerful technique in pre-clinical and clinical settings. To overcome these limitations, the goal of this thesis is to develop an entirely new approach termed, "Temperature-modulated fluorescence tomography (TM-FT)", that can provide high resolution images at depths up to 6 cm without sacrificing the exceptional sensitivity of FT. In this innovative approach, FT is combined with temperature activatable fluorescence molecular probes (ThermoDots) and high intensity focused ultrasound (HIFU) which can provide localized heating of the tissue (only 3-5 °C) with high spatial resolution. The small size of the focal spot (~1.4 mm) allows imaging the distribution of these temperature sensitive agents with not only high spatial resolution but also high quantitative accuracy.This thesis will present the development of the first TM-FT system prototype including the instrumentation and system design, image reconstruction algorithm, and ThermoDots probe development. The feasibility of this method to provide superior spatial resolution and high quantitative accuracy is validated using simulations and experimentally demonstrated in phantom and ex vivo tissue.

Download or read book New Approaches to Higher Resolution Imaging in Diffuse Optical Tomography written by Ari Goldberg and published by . This book was released on 2004 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A True Multi modality System for Optical Imaging with MR Resolution written by Alex T. Luk and published by . This book was released on 2016 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major goal of in vivo imaging is to obtain individualized structural, functional, and molecular information to provide personalized medicine. In particular, optical imaging uses non-ionizing radiation to provide functional information such as hemoglobin concentration and also visualize exogenous contrast agents as well as molecular and functional markers. Indeed, in vivo optical imaging extends across a wide range of applications, from cellular to organ levels. At high end of the spectrum, diffuse optical tomography (DOT) can penetrate up to 10 centimeters but only offer low-resolution images (> 5mm) due to highly scattering nature of the tissue.Significant effort has been spent on multi-modality imaging techniques to improve the resolution of DOT. While combining DOT with spatial information defined by a separate anatomical imaging modality is promising, there are many challenges and inaccuracies that arise with co-registration. However this can be overcome with a novel multi-modality imaging technique, Photo-Magnetic Imaging (PMI) which uses MRI as a detector to provide both high resolution anatomical and optical information. PMI takes advantage of the 3D measurement capabilities of MR thermometry (MRT) to non-invasively measure the temperature increase of the medium induced by a laser to acquire a temperature map of the entire volume. As DOT measures the photon flux only from the boundary, the major advantage of PMI is that high absorbing regions can be resolved directly from the high spatial resolution temperature map. These measurements can then be converted to obtain the optical absorption properties of the tissue using a reconstruction algorithm to model the light propagation and heat transfer in tissue.This thesis will present the development of the first preclinical in vivo small animal PMI system prototype using the safety standards set by the American National Standard Institution. To optimize the system for in vivo studies, a fast PMI reconstruction method was also developed to accelerate the original PMI reconstruction method ~1000 times faster. These promising results validated the practicality of PMI for preclinical studies and showed the potential of PMI for clinical studies. This led to the development of the first human PMI prototype for clinical breast studies.

Download or read book Advances in Optical Imaging for Clinical Medicine written by Nicusor Iftimia and published by John Wiley & Sons. This book was released on 2011-04-27 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides students, teachers, researchers and clinicians with a strong and established source of information on advanced optical technologies that show real promise of being translated to clinical use.

Download or read book Photomagnetic Imaging written by David A. Thayer and published by . This book was released on 2011 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomedical imaging has played an increasingly important role over the past several decades, contributing to improved medical diagnosis, treatment, and therapy monitoring as well as facilitating basic science discovery. Optical imaging modalities have and will continue to play an important part in this development. Current imaging modalities such as magnetic resonance imaging (MRI), ultrasound (US), and computed tomography (CT) produce very high-resolution images with penetration depths sufficient for human imaging, but have little intrinsic sensitivity to metabolism. Near-infrared optical imaging modalities, on the other hand, are intrinsically sensitive to tissue metabolism through the principle near-infrared absorbers: fat, water, hemoglobin and deoxyhemoglobin. The overall and relative amounts of the last two are directly related to tissue metabolism. This information can complement the high-resolution anatomic information provided by MRI, US, and CT. In cancer imaging, for example, MRI is highly sensitive in detecting cancer, but has significantly lower specificity, resulting in unnecessary biopsy of benign lesions. The functional information provided by optical imaging modalities, like diffuse optical tomography (DOT), can improve this specificity. DOT, unfortunately, is limited by its poor resolution and ill-posedness, making accurate recovery of tissue optical properties difficult. Photoacoustic tomography (PAT) is an emerging hybrid modality which has successfully coupled laser illumination with ultrasonic detection to provide high-resolution functional images, albeit with limited depth penetration and significant performance degradation without probe contact. This dissertation introduces Photomagnetic Imaging (PMI) for the first time, which is a new, hybrid optical imaging modality combining laser illumination with high-sensitivity magnetic resonance (MR) thermometry. It provides the same useful information as DOT and PAT, but at MRI resolution, and without the need for contact. This dissertation presents the basic theory, hardware, and modeling of PMI, compares it to current modalities, presents experiments characterizing its performance, shows phantom and preliminary animal imaging results, and introduces an alternative acquisition scheme, termed synchronized k-line imaging (SKI-PMI) which improves some aspects of PMI. Also presented is an analysis of potential applications for this new modality. Data was collected using multiple agar phantoms with high-absorption inclusions. Results show that PMI has high potential as a new optical imaging modality.

Download or read book Optical Methods and Instrumentation in Brain Imaging and Therapy written by Steen J. Madsen and published by Springer Science & Business Media. This book was released on 2012-11-13 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive up-to-date review of optical approaches used in brain imaging and therapy. It covers a variety of imaging approaches including diffuse optical imaging, laser speckle imaging, photoacoustic imaging and optical coherence tomography. A number of laser-based therapeutic techniques are reviewed, including photodynamic therapy, fluorescence guided resection and photothermal therapy. Fundamental principles and instrumentation are discussed for each imaging and therapeutic approach.

Download or read book Translational Multimodality Optical Imaging written by Fred S. Azar and published by Artech House. This book was released on 2008 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supported with 119 illustrations, this milestone work discusses key optical imaging techniques in self-contained chapters; describes the integration of optical imaging techniques with other modalities like MRI, X-ray imaging, and PET imaging; provides a software platform for multimodal integration; presents cutting-edge computational and data processing techniques that ensure rapid, cost-effective, and precise quantification and characterization of the clinical data; covers advances in photodynamic therapy and molecular imaging, and reviews key clinical studies in optical imaging along with regulatory and business issues.

Download or read book High resolution Three D Diffuse Optical Tomography for Non invasive Functional Brain Imaging in the Sub centimeter Range written by and published by . This book was released on 2014 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Diffuse Optical Tomography Methods for Imaging the Developing Brain written by Silvina Laura Ferradal and published by . This book was released on 2014 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffuse optical imaging (DOI) is a portable imaging modality that provides the ability to perform early and continuous monitoring of brain function in infants. Its methodology overcomes many of the technical and logistical challenges of performing magnetic resonance imaging (MRI) investigations in neonates. However, standard DOI systems suffer from limitations such as low spatial resolution and contamination of hemodynamic signals originating from superficial tissue layers that affect the overall reliability of the optical measurements. Recent advances in the application of high-density diffuse optical tomography (HD-DOT) in adults have overcome most of these limitations by using high-density arrays of overlapping measurements that improve spatial resolution and brain specificity. My doctoral work has been focused on the development of HD-DOT methods for bedside neuroimaging in neonates. While HD-DOT enables image reconstructions with improved image quality, the design and implementation of high-density arrays for newborn infants involves challenges related to cap ergonomics and bulkiness of the fiber bundles. The first part of my dissertation demonstrates the feasibility of using a custom-built HD-DOT system with a limited field of view for imaging brain function in a clinical environment such as the neonatal intensive care unit (NICU). Using stimulus-driven paradigms such as visual stimulation and advanced imaging techniques such as resting state functional connectivity, I show that HD-DOT can perform functional mapping of the visual cortex in hospitalized infants. Resting state functional connectivity methods are particularly suited for studying hospitalized infants who cannot perform complex tasks. Accordingly, the second part of my dissertation was focused on the development of an extended field of view system for simultaneous functional connectivity DOT (fcDOT) mapping of multiple functional regions. In parallel with the hardware expansion, I developed techniques for realistic forward light modeling and spatial normalization that facilitate anatomical registration between different subjects and imaging modalities. The proposed techniques were validated in vivo against subject-matched functional MRI maps, the gold standard for functional neuroimaging. The strong spatial agreement between individual and group maps obtained for both modalities suggests that fcDOT provides satisfactory spatial localization and resolution for imaging neonates at the bedside. While in most cases it is desirable to use subject-specific structural images for accurate DOT reconstruction, this approach is not sufficient for portable applications. In the last part of my dissertation, I explored the feasibility of using anatomical atlases for forward light modeling. Quantitative comparisons with functional MRI show that atlas-based image reconstruction provides a viable approach to individual head modeling for HD-DOT when anatomical imaging is not available.

Download or read book New Horizons in Time Domain Diffuse Optical Spectroscopy and Imaging written by Yoko Hoshi and published by MDPI. This book was released on 2020-06-23 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jöbsis was the first to describe the in vivo application of near-infrared spectroscopy (NIRS), also called diffuse optical spectroscopy (DOS). NIRS was originally designed for the clinical monitoring of tissue oxygenation, and today it has also become a useful tool for neuroimaging studies (functional near-infrared spectroscopy, fNIRS). However, difficulties in the selective and quantitative measurements of tissue hemoglobin (Hb), which have been central in the NIRS field for over 40 years, remain to be solved. To overcome these problems, time-domain (TD) and frequency-domain (FD) measurements have been tried. Presently, a wide range of NIRS instruments are available, including commonly available commercial instruments for continuous wave (CW) measurements, based on the modified Beer–Lambert law (steady-state domain measurements). Among these measurements, the TD measurement is the most promising approach, although compared with CW and FD measurements, TD measurements are less common, due to the need for large and expensive instruments with poor temporal resolution and limited dynamic range. However, thanks to technological developments, TD measurements are increasingly being used in research, and also in various clinical settings. This Special Issue highlights issues at the cutting edge of TD DOS and diffuse optical tomography (DOT). It covers all aspects related to TD measurements, including advances in hardware, methodology, the theory of light propagation, and clinical applications.

Download or read book A Diffuse Optical Tomography System Combined with X ray Mammography for Improved Breast Cancer Detection written by Thomas John Brukilacchio and published by . This book was released on 2003 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: The central thesis of this dissertation states that optical imaging of diffuse tissues must be combined in co-registration with a recognized gold standard of mammographic screening, i.e. X-ray mammography, to gain wide acceptance in the clinical environment. This multi-modality imaging approach promises to overcome the deficiencies of both imaging modalities by drawing on the strengths of each. Functional and structural image contrast would be provided by optical and high-resolution structural contrast by X-ray. Furthermore, the structural information provided by X-ray could be used to improve the optical image reconstruction by providing boundary information and soft constraints for weakly correlated structural contrast. Ultimately, image-processing techniques could be developed to provide the radiologist with a three-dimensional image indicative of both optical and X-ray contrast that would provide much greater information content than either modality alone.

Download or read book High resolution Optical Imaging written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Biomedical Image Analysis written by Mark Haidekker and published by John Wiley & Sons. This book was released on 2011-03-29 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference of cutting-edge advanced techniques for quantitative image processing and analysis Medical diagnostics and intervention, and biomedical research rely progressively on imaging techniques, namely, the ability to capture, store, analyze, and display images at the organ, tissue, cellular, and molecular level. These tasks are supported by increasingly powerful computer methods to process and analyze images. This text serves as an authoritative resource and self-study guide explaining sophisticated techniques of quantitative image analysis, with a focus on biomedical applications. It offers both theory and practical examples for immediate application of the topics as well as for in-depth study. Advanced Biomedical Image Analysis presents methods in the four major areas of image processing: image enhancement and restoration, image segmentation, image quantification and classification, and image visualization. In each instance, the theory, mathematical foundation, and basic description of an image processing operator is provided, as well as a discussion of performance features, advantages, and limitations. Key algorithms are provided in pseudo-code to help with implementation, and biomedical examples are included in each chapter. Image registration, storage, transport, and compression are also covered, and there is a review of image analysis and visualization software. Members of the academic community involved in image-related research as well as members of the professional R&D sector will rely on this volume. It is also well suited as a textbook for graduate-level image processing classes in the computer science and engineering fields.

Download or read book XIII Mediterranean Conference on Medical and Biological Engineering and Computing 2013 written by Laura M. Roa Romero and published by Springer Science & Business Media. This book was released on 2013-10-01 with total page 1978 pages. Available in PDF, EPUB and Kindle. Book excerpt: The general theme of MEDICON 2013 is "Research and Development of Technology for Sustainable Healthcare". This decade is being characterized by the appearance and use of emergent technologies under development. This situation has produced a tremendous impact on Medicine and Biology from which it is expected an unparalleled evolution in these disciplines towards novel concept and practices. The consequence will be a significant improvement in health care and well-fare, i.e. the shift from a reactive medicine to a preventive medicine. This shift implies that the citizen will play an important role in the healthcare delivery process, what requires a comprehensive and personalized assistance. In this context, society will meet emerging media, incorporated to all objects, capable of providing a seamless, adaptive, anticipatory, unobtrusive and pervasive assistance. The challenge will be to remove current barriers related to the lack of knowledge required to produce new opportunities for all the society, while new paradigms are created for this inclusive society to be socially and economically sustainable, and respectful with the environment. In this way, these proceedings focus on the convergence of biomedical engineering topics ranging from formalized theory through experimental science and technological development to practical clinical applications.

Download or read book Biomedical Optical Imaging Technologies written by Rongguang Liang and published by Springer Science & Business Media. This book was released on 2012-09-21 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to design of biomedical optical imaging technologies and their applications. The main topics include: fluorescence imaging, confocal imaging, micro-endoscope, polarization imaging, hyperspectral imaging, OCT imaging, multimodal imaging and spectroscopic systems. Each chapter is written by the world leaders of the respective fields, and will cover: principles and limitations of optical imaging technology, system design and practical implementation for one or two specific applications, including design guidelines, system configuration, optical design, component requirements and selection, system optimization and design examples, recent advances and applications in biomedical researches and clinical imaging. This book serves as a reference for students and researchers in optics and biomedical engineering.

Download or read book Diffuse Optical Tomography written by Huabei Jiang and published by CRC Press. This book was released on 2010-12-07 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an authority involved in the field since its nascent stages, Diffuse Optical Tomography: Principles and Applications is a long-awaited profile of a revolutionary imaging method. Diffuse Optical Tomography (DOT) provides spatial distributions of intrinsic tissue optical properties or molecular contrast agents through model-based reconstruction algorithms using NIR measurements along or near the boundary of tissue. Despite the practical value of DOT, many engineers from electrical or applied mathematics backgrounds do not have a sufficient understanding of its vast clinical applications and portability value, or its uncommon advantages as a tool for obtaining functional, cellular, and molecular parameters. A collection of the author’s research and experience, this book fuses historical perspective and experiential anecdotes with fundamental principles and vital technical information needed to successfully apply this technology—particularly in medical imaging. This reference finally outlines how to use DOT to create experimental image systems and adapt the results of laboratory studies for use in clinical applications including: Early-stage detection of breast tumors and prostate cancer "Real-time" functional brain imaging Joint imaging to treat progressive diseases such as arthritis Monitoring of tumor response New contrast mechanisms and multimodality methods This book covers almost every aspect of DOT—including reconstruction algorithms based on nonlinear iterative Newton methods, instrumentation and calibration methods in both continuous-wave and frequency domains, and important issues of imaging contrast and spatial resolution. It also addresses phantom experiments and the development of various image-enhancing schemes, and it describes reconstruction methods based on contrast agents and fluorescence DOT. Offering a concise description of the particular problems involved in optical tomography, this reference illustrates DOT’s fundamental foundations and the principle of image reconstruction. It thoroughly explores computational methods, forward mathematical models, and inverse strategies, clearly illustrating solutions to key equations.

Download or read book Biophotonics in Pathology written by S. Cohen and published by IOS Press. This book was released on 2013-04-11 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photonics is a term often used in relation to light-based circuits, but it is actually more inclusive, including the generation, emission, transmission, modulation and signal processing of light. Biophotonics is therefore a term which can be used to describe the development and application of optical techniques for the study of biological molecules, cells and tissues. This book presents some of the most promising new image-based and related technologies which have evolved in the last few years for the study, visualization, characterisation and analysis of abnormal cells and tissues, and discusses their current and potential applications in experimental pathology and clinical pathological diagnosis. The book contains more than a dozen papers contributed by experts in the field, and the technology is described in a manner accessible to an audience of pathologists, cell biologists and biochemists as well as biomedical engineers. Subjects covered include: advanced methods in fluorescence microscopy, automated image interpretation and computer-assisted diagnostics, magnetic resonance microscopy, impedence measurements in the biomedical sciences and raman scattering in pathology, among others. There is an increasing convergence of radiology and pathology, and although this book has been written from the perspective of pathology, it demonstrates a confluence of methodologies similar to those applied in radiology with morphological analysis at the cellular and tissue level, and will also be of interest to radiologists, as well as to other scientists and engineers working in overlapping areas.