Download or read book Novel Nonlinear Optics and Quantum Optics Approaches for Ultrasound modulated Optical Tomography in Soft Biological Tissue written by Huiliang Zhang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical imaging of soft biological tissue is highly desirable since it is nonionizing and provides sensitive contrast information which enables the detection of physiological functions and abnormalities, including potentially early cancer detection. However, due to the diffusive nature of light in soft biological tissue, it is difficult to achieve simultaneously good spatial resolution and good imaging depth with pure optical imaging modalities. This work focuses on the ultrasound-modulated optical tomography (UOT): a hybrid technique which combines the advantages of ultrasonic resolution and optical contrast. In this technique, focused ultrasound and optical radiation of high temporal coherence are simultaneously applied to soft biological tissue. The intensity of the sideband, or ultrasound "tagged" photons depends on the optical absorption in the region of interest where the ultrasound is focused. Demodulation of the optical speckle pattern yields the intensity of tagged photons for each location of the ultrasonic focal spot. Thus UOT yields an image with spatial resolution of the focused ultrasound -- typically submillimeter -- whose contrast is related to local optical absorption and the diffusive properties of light in the organ. Thus it extends all the advantages of optical imaging deep into highly scattering tissue. However lack of efficient tagged light detection techniques has so far prevented ultrasound-modulated optical tomography from achieving maturity. The signal-to-noise ratio (SNR) and imaging speed are two of the most important figures of merit and need further improvement for UOT to become widely applicable. In the first part of this work, nonlinear optics detection methods have been implemented to demodulate the "tagged" photons. The most common of these is photorefractive (PR) two wave mixing (TWM) interferometry, which is a time-domain filtering technique. When used for UOT, it is found that this approach extracts not only optical properties but also mechanical properties for the area of interest. To improve on TWM, PR four wave mixing (FWM) experiments were performed to read out only the modulated light and at the same time strongly suppressing the "untagged" light. Spectral-hole burning (SHB) in a rare-earth-ion-doped crystal has been developed for UOT more recently. Experiments in Tm3 :Y3Al5O12 (Tm:YAG) show the outstanding features of SHB: large angle acceptance (etendue), light speckle processing in parallel (insensitive to the diffusive light nature) and real-time signal collection (immune to light speckle decorrelation). With the help of advanced laser stabilization techniques, two orders of magnitude improvement of SNR have been achieved in a persistent SHB material (Pr3 :Y2SiO5) compared to Tm:YAG. Also slow light with PSHB further reduces noise in Pr:YSO UOT that is caused by polarization leakage by performing time-domain filtering.
Download or read book El Tirano de Lombardia written by and published by . This book was released on 1790* with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Biophotonics written by Ruikang K. Wang and published by Taylor & Francis. This book was released on 2016-04-19 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite a number of books on biophotonics imaging for medical diagnostics and therapy, the field still lacks a comprehensive imaging book that describes state-of-the-art biophotonics imaging approaches intensively developed in recent years. Addressing this shortfall, Advanced Biophotonics: Tissue Optical Sectioning presents contemporary methods and
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 Optical Coherence Tomography written by Wolfgang Drexler and published by Springer Science & Business Media. This book was released on 2008-12-10 with total page 1346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical coherence tomography (OCT) is the optical analog of ultrasound imaging and is emerging as a powerful imaging technique that enables non-invasive, in vivo, high resolution, cross-sectional imaging in biological tissue. This book introduces OCT technology and applications not only from an optical and technological viewpoint, but also from biomedical and clinical perspectives. The chapters are written by leading research groups, in a style comprehensible to a broad audience.
Download or read book Ultrasound encoded Optical Tomography and Time reversed Ultrasonically Encoded Optical Focusing written by Xiao Xu and published by . This book was released on 2011 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultrasound modulated optical tomography is a developing hybrid imaging modality that combines high optical contrast and good ultrasonic resolution to image soft biological tissue. We developed a photorefractive crystal-based, time-resolved detection scheme with the use of a millisecond long ultrasound burst to image both the optical and mechanical properties of biological tissues, with improved detection efficiency of ultrasound-tagged photons. We also applied spectral-hole burning (SHB) aided detection in ultrasound-modulated optical tomography (UOT) to image optical heterogeneities in thick tissue-mimicking phantom samples and chicken breast tissue. The efficiency of SHB was improved by using a Tm3+: YAG crystal of higher doping concentration (2.0-atomic%) and a double-pass pumping configuration. With the improved SHB-UOT system, we imaged absorbing, scattering, and phase contrast objects that were embedded in the middle plane of a 30-mm thick phantom sample. The imaging resolution was 0.5 mm in the lateral direction, as defined by the focal width of the ultrasonic transducer, and 1.5 mm in the axial direction, as determined by the ultrasonic burst length. We also imaged two absorbing objects embedded in the middle plane of a 32-mm thick chicken breast sample. The results suggest that the improved SHB-UOT system is one step closer to a practical optical imaging application in biological and clinical studies. Light focusing plays a central role in biomedical imaging, manipulation, and therapy. In optical scattering media such as biological tissue, light propagation is randomized by multiple scattering. Beyond one transport mean free path, where photon propagation is in the diffusive regime, direct light focusing becomes infeasible. Although various methods have been developed to overcome this optical diffusion limit, all are limited by the lack of a practical internal "guide star." Here we proposed and experimentally validated a novel concept, called Time-Reversed Ultrasonically Encoded (TRUE) optical focusing, to deliver light dynamically into any predefined location inside a scattering medium. First, diffused coherent light is encoded by an ultrasonic wave focused to a predefined location; then, the encoded component of the diffused light is time-reversed and consequently converges back to the ultrasonic focus. The ultrasonic encoding noninvasively provides a virtual internal "guide star" for the time reversal. The TRUE optical focus--dynamically defined by the ultrasonic focus--is unaffected by multiple scattering of light, which is especially desirable in biological tissue where ultrasonic scattering is ~1000 times weaker than optical scattering. Various fields, such as biomedical, colloidal, atmospheric, and ocean optics, can benefit from TRUE optical focusing. Further, the concept can be generalized for non-optical waves.
Download or read book Biomedical and Resonance Optics written by Leonid V. Tanin and published by Springer Nature. This book was released on 2020-12-10 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses fundamentally new biomedical imaging methods, such as holography, holographic and resonant interferometry, and speckle optics. It focuses on the development of holographic interference microscopy and its use in the study of phase objects such as nerve and muscle fibers subjected to the influence of laser radiation, magnetic fields, and hyperbaric conditions. The book shows how the myelin sheath and even the axon itself exhibit waveguide properties, enabling a fresh new look at the mechanisms of information transmission in the human body. The book presents theoretically and experimentally tested holographic and speckle-optical methods and devices used for investigating complex, diffusely scattering surfaces such as skin and muscle tissue. Additionally, it gives broad discussion of the authors’ own original fundamental and applied research dedicated to helping physicians introduce new contact-less methods of diagnosis and treatment of diseases of the cardiovascular and neuromuscular systems into medical practice. The book is aimed at a broad spectrum of scientific specialists in the fields of speckle optics, holography, laser physics, morphology and cytochemistry, as well as medical professionals such as physiologists, neuropathologists, neurosurgeons, cardiologists and dentists.
Download or read book Optical Imaging in Human Disease and Biological Research written by Xunbin Wei and published by Springer Nature. This book was released on 2021-05-29 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book introduces readers to the basic principle of optical imaging technologies. Focusing on human disease diagnostics using optical imaging methods, it provides essential information for researchers in various fields and discusses the latest trends in optical imaging. In recent decades, there has been a huge increase in imaging technologies and their applications in human diseases diagnostics, including magnetic resonance imaging, x-ray computed tomography, and nuclear tomographic imaging. This book promotes further developments to extend optical imaging to a wider range of disease diagnostics. It is a valuable resource for researchers and students in the field of biomedical optics, as well as for clinicians.
Download or read book Optics and Ultrasound in Biomedicine Sensing Imaging and Therapy written by Chao Tian and published by Frontiers Media SA. This book was released on 2021-07-22 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Tissue Optical Clearing written by Valeriĭ Viktorovich Tuchin and published by . This book was released on 2021-11 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Biomedical photonics is currently one of the fastest growing fields, connecting research in physics, optics, and electrical engineering coupled with medical and biological applications. It allows for the structural and functional analysis of tissues and cells with resolution and contrast unattainable by any other methods. However, the major challenges of many biophotonics techniques are associated with the need to enhance imaging resolution even further to the sub-cellular level as well as translate them for in vivo studies. The tissue optical clearing method uses immersion of tissues into optical clearing agents (OCAs) that reduces the scattering of tissue and makes tissue more transparent and this method has been successfully used ever since. This book is a self-contained introduction to tissue optical clearing, including the basic principles and in vitro biological applications, from in vitro to in vivo tissue optical clearing methods, and combination of tissue optical clearing and various optical imaging for diagnosis. The chapters cover a wide range of issues related to the field of tissue optical clearing: mechanisms of tissue optical clearing in vitro and in vivo; traditional and innovative optical clearing agents; recent achievements in optical clearing of different tissues (including pathological tissues) and blood for optical imaging diagnosis and therapy. This book provides a comprehensive account of the latest research and possibilities of utilising optical clearing as an instrument for improving the diagnostic effectiveness of modern optical diagnostic methods. The book is addressed to biophysicist researchers, graduate students and postdocs of biomedical specialties, as well as biomedical engineers and physicians interested in the development and application of optical methods in medicine. Key features: The first collective reference to collate all known knowledge on this topic Edited by experts in the field with chapter contributions from subject area specialists Brings together the two main approaches in immersion optical clearing into one cohesive book"--
Download or read book Coherent Domain Optical Methods written by Valery V. Tuchin and published by Springer Science & Business Media. This book was released on 2004-10-15 with total page 963 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the first time in one set of books, coherent-domain optical methods are discussed in the framework of various applications, which are characterized by a strong light scattering. A few chapters describe basic research containing the updated results on coherent and polarized light non-destructive interactions with a scattering medium, in particular, diffraction, interference, and speckle formation at multiple scattering. These chapters allow for understanding coherent-domain diagnostic techniques presented in later chapters. A large portion of Volume I is dedicated to analysis of various aspects of optical coherence tomography (OCT) - a very new and growing field of coherent optics. Two chapters on laser scanning confocal microscopy give insight to recent extraordinary results on in vivo imaging and compare the possibilities and achievements of confocol, excitation multiphoton, and OCT microscopy. This two volume reference contains descriptions of holography, interferometry and optical heterodyning techniques in their application for diagnostics of turbid materials. The most prospective methods of coherent and polarization optical imaging and spectroscopy, including polarization-sensitive optical coherent tomography, polarization diffusion wave spectroscopy, and elastic and quasi-elastic light scattering spectroscopies and image techniques, are presented.
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 Tissue Optics written by Valeriĭ Viktorovich Tuchin and published by SPIE-International Society for Optical Engineering. This book was released on 2000 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: This tutorial text explores light-scattering techniques developed for studies of tissues and optical cell ensembles. It discusses results of theoretical and experimental investigations into photon transport in tissues and describes methods for solving direct and inverse scattering problems involving different types of tissues and fluids (opaque vs transparent).
Download or read book D w n i r Ba r b Burd written by and published by . This book was released on 1964 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Proceedings of Optical Tomography and Spectroscopy of Tissue III written by Britton Chance and published by SPIE-International Society for Optical Engineering. This book was released on 1999 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomedical Optics written by and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
