Download or read book A Continuous Wave Diffusion Optical Tomography System Based on High Accuracy Multidimensional Imaging Reconstruction Model for Breast Tumor Detection written by and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Continuous wave Optical Diffuse Tomography for Breast Cancer Detection written by Xuejun Gu and published by . This book was released on 2003 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Topics in Photonics written by Asima Pradhan and published by Springer. This book was released on 2017-10-27 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume comprises chapters on the cutting-edge research in photonics undertaken at IIT Kanpur. Photonics requires scientists and engineers to work closely together in addressing challenges which are interdisciplinary in nature. At IIT Kanpur, research is being pursued in several key areas of photonics namely fiber-optics, nanophotonics, quantum optics, optical spectroscopy and imaging, biophotonics, and photonic devices. This volume brings together contributions from experts to obtain a contemporary perspective in photonics research. The reader will find articles about coherent optical communications, novel photonic nanostructures, nano-structured materials for light control, optical tweezers with nanoscale applications, quantum coherence and entanglement, photodiode arrays and quantum metrology. The volume also includes chapters on cancer diagnostics with optical tomography, protein fluctuations at microsecond scale at single-molecule level, and visualization of motion in a droplet which are interdisciplinary in nature. The contents of this book will be of use to researchers, students, and professionals working across all domains of photonics.

Download or read book Deep Learning Methods for Reconstruction and Analysis of Diffuse Optical Tomography Images of Breast Cancer Lesions written by Hanene Ben Yedder and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of an accurate, efficient, portable, and affordable method for identifying breast cancer is critical for both early detection and improved prognosis. Medical imaging modalities play a critical role in cancer screening and treatment monitoring. Diffuse optical tomography (DOT) is a non-invasive imaging modality that can be used in a low-complexity probe design, resulting in an inexpensive portable imaging diagnostic device with low power consumption. In recent years, machine learning techniques have created transformative opportunities for medical image reconstruction and analysis, helping move toward data-driven algorithm designs wherein computational power is augmented with physics priors to push the accuracy and fairness of image driven diagnosis to new limits. In this thesis, we present multiple deep learning-based medical image reconstruction and analysis approaches for screening breast cancer lesions acquired by DOT. First, an end-to-end image reconstruction model from sensor-domain data is proposed, where physics-based simulation is leveraged to address the lack of available real-world data required for training. Next, we adopt a transfer learning strategy to align and translate the sensor domain distribution between in silico and real-world data and propose a novel loss to promote appearance similarity and penalize artifacts. Following up on this we propose a joint reconstruction and localization solution that simultaneously attends to the most important features while ensuring better lesion localization. Finally, we propose an orthogonal multi-frequency fusion solution for direct prediction of the end task from sensor signal data, increasing diagnosis accuracy at a reduced computational cost. Extending a portable device with such diagnosis ability promises to improve first-line treatment throughput. These contributions demonstrate the promising role of deep learning in DOT image reconstruction and diagnosis. Combined, our contributions open the path towards personalized medicine for non-invasive portable diagnosis and treatment monitoring of breast cancer in the very near future.

Download or read book Optics Letters written by and published by . This book was released on 2003 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Diffuse Optical Tomography System in Soft Tissue Tumor Detection written by Umamaheswari Kumarasamy and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Topical review of recent trends in Modeling and Regularization methods of Diffuse Optical Tomography (DOT) system promotes the optimization of the forward and inverse modeling methods which provides a 3D cauterization at a faster rate of 40frames/second with the help of a laser torch as a hand-held device. Analytical, Numerical and Statistical methods are reviewed for forward and inverse models in an optical imaging modality. The advancement in computational methods is discussed for forward and inverse models along with Optimization techniques using Artificial Neural Networks (ANN), Genetic Algorithm (GA) and Artificial Neuro Fuzzy Inference System (ANFIS). The studies carried on optimization techniques offers better spatial resolution which improves quality and quantity of optical images used for morphological tissues comparable to breast and brain in Near Infrared (NIR) light. Forward problem is based on the location of sources and detectors solved statistically by Monte Carlo simulations. Inverse problem or closeness in optical image reconstruction is moderated by different regularization techniques to improve the spatial and temporal resolution. Compared to conventional methods the ANFIS structure of optimization for forward and inverse modeling provides early detection of Malignant and Benign tumor thus saves the patient from the mortality of the disease. The ANFIS technique integrated with hardware provides the dynamic 3D image acquisition with the help of NIR light at a rapid rate. Thereby the DOT system is used to continuously monitor the Oxy and Deoxyhemoglobin changes on the tissue oncology.

Download or read book A High Efficiency System on Chip Design for Portable Continuous Wave Diffusion Optical Tomography System written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ultrasound Guided Diffuse Optical Tomography for Breast Cancer Diagnosis written by K. M. Shihab Uddin and published by . This book was released on 2020 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: According to National Breast Cancer Society, one in every eight women in United States is diagnosed with breast cancer in her lifetime. American Cancer Society recommends a semi-annual breast-cancer screening for every woman which can be heavily facilitated by the availability of low-cost, non-invasive diagnostic method with good sensitivity and penetration depth. Ultrasound (US) guided Diffuse Optical Tomography (US-guided DOT) has been explored as a breast-cancer diagnostic and screening tool over the past two decades. It has demonstrated a great potential for breast-cancer diagnosis, treatment monitoring and chemotherapy-response prediction. In this imaging method, optical measurements of four different wavelengths are used to reconstruct unknown optical absorption maps which are then used to calculate the hemoglobin concentration of the US-visible lesion. This dissertation focuses on algorithm development for robust data processing, imaging reconstruction and optimal breast cancer diagnostic strategy development in DOT. The inverse problem in DOT is ill-posed, ill-conditioned, and underdetermined. This makes the task of image reconstruction challenging, and thus regularization-based method need to be employed. In this dissertation, a simple two-step reconstruction method that can produce accurate image estimates in DOT is proposed and investigated. In the first step, a truncated Moore-Penrose Pseudoinverse solution is computed to obtain a preliminary estimate of the image. This estimate can be reliably determined from the measured data; subsequently, this preliminary estimate is incorporated into the design of a penalized least squares estimator that is employed to compute the final image estimate. Using physical phantoms, the proposed method was demonstrated to yield more accurate reconstruction compared to other conventional reconstruction methods. The method was also evaluated with clinical data that included 10 benign and 10 malignant cases. The capability of reconstructing high contrast malignant lesions improved by the use of the proposed method.Reconstructed absorption maps are prone to image artifacts from outliers in measurement data from tissue heterogeneity, bad coupling between tissue and light guides, and motion by patient or operator. In this dissertation, a new automated iterative perturbation correction algorithm is proposed to reduce image artifacts based on the structural similarity index (SSIM)) of absorption maps of four optical wavelengths. The SSIM was calculated for each wavelength to assess its similarity with other wavelengths. Absorption map was iteratively reconstructed and projected back into measurement space to quantify projection error. Outlier measurements with highest projection errors were iteratively removed until all wavelength images were structurally similar with SSIM values greater than a threshold. Clinical data demonstrated statistically significant improvement in image artifact reduction.US guidance with DOT helps to reduce false positive rate and hence reduce number of unnecessary biopsies. However, DOT data processing and image reconstruction speed remains slow compared to real-time US. Real-time or near real time diagnosis with DOT is an important step toward the clinical translation of the US-guided DOT. In this dissertation, to address this important need, we present a two-stage diagnostic strategy that is computationally efficient and accurate. In the first stage, benign lesions are identified in near real-time by use of a random forest classifier acting on the DOT measurements and radiologists' US diagnostic scores. The lesions that cannot be reliably classified by the random forest classifier will be passed on to the image reconstruction stage. Functional information from the reconstructed hemoglobin concentrations is used by a Support Vector Machine (SVM) classifier for diagnosis in the second stage. This two-step classification approach that combines both perturbation data and functional features results in improved classification, as quantified using the receiver operating characteristic (ROC) curve. Using this two-step approach, area under the ROC curve (AUC) is 0.937 ± 0.009 with sensitivity of 91.4% and specificity of 85.7%. While using functional features and US score, AUC is 0.892 ± 0.027 with sensitivity of 90.2% and specificity of 74.5%. The specificity increased by more than 10% due to the implementation of the random forest classifier.

Download or read book Methods for Improving the Reconstruction of Diffuse Optical Tomography for Breast Cancer Detection written by Murad Mohsen Althobaiti and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Real Time Handheld 3 D Imaging System Based on Diffuse Optical Tomography for Measuring Early stage Breast Tumor written by and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Multimodal Breast Cancer Imaging System Using Coregistered Dynamic Diffuse Optical Tomography and Digital Breast Tomosynthesis written by Bernhard B. Zimmermann and published by . This book was released on 2017 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffuse optical tomography (DOT) is an emerging noninvasive functional imaging method for breast cancer diagnosis and neoadjuvant chemotherapy monitoring. In particular, the multimodal approach of combining DOT with x-ray digital breast tomosynthesis (DBT) is especially synergistic as DBT prior information can be used to enhance the DOT reconstruction. DOT, in turn, provides a functional information overlay onto the mammographic images, increasing sensitivity and specificity to cancer pathology. We describe a dynamic DOT apparatus designed for tight integration with commercial DBT scanners and providing a fast (1 Hz+) image acquisition rate to enable tracking of hemodynamic changes induced by the mammographic breast compression. The most significant advance enabling fast acquisition was the design and construction of a direct analog-to-digital conversion frequency-domain near-infrared spectroscopy (FD-NIRS) component. It achieves simultaneous dual wavelength operation at 685 nm and 830 nm by concurrent 67.5 MHz and 75 MHz frequency modulation of each laser source, respectively, followed by digitization using a high-speed analog to digital converter and real-time hybrid FPGA-assisted demodulation by discrete Fourier transform (DFT). The overall DOT system integrates 96 CW-NIRS and 24 FD-NIRS source locations, as well as 32 CW-NIRS and 20 FD-NIRS detection locations into low-profile plates that mate to the DBT compression paddle and x-ray detector cover, respectively. The plates and the embedded optical fibers are made of plastic to minimize x-ray absorption and thus allow true simultaneous acquisition of the DBT image. We first characterize each major system component individually, and then demonstrate overall performance using static and dynamic tissue-like phantoms, as well as in vivo images acquired from the pool of patients recalled for breast biopsies at the Massachusetts General Hospital Breast Imaging Division.

Download or read book Parallel rapid diffuse optical tomography of breast written by and published by . This book was released on 2002 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last year we have experimentally and computationally investigated rapid acquisition and analysis of informationally dense diffuse optical data sets in the parallel plate compressed breast geometry. We have developed and tested a 3-dimensional image reconstruction algorithm for the diffusive wave inverse problem that runs on a parallel computer cluster. This code uses a finite difference method in the forward calculation, a novel Integro-Differential equation, previously developed by this group, in the reconstruction. There has been a significant improvement in our instrumentation and measurement capabilities. A hybrid RF/CW diffuse optical tomography (DOT) system measures limited number of frequency-domain reemission data and significantly larger continuous wave transmission data by a lens coupled CCD simultaneously. The wavelength of the light source is optically switched from 690, 750, 786 and 830 nm and then its position is switched among 45 different positions on the compression plate. The instrument and reconstruction algorithm performance have been tested using small silicone tissue phantoms as a tumor of various size and optical properties suspended into the liquid tissue phantom. The study of the effect of boundary between the matching fluid and breast has been initiated by building and taking measurements from tissue phantoms with breast shape, embedded with small objects with higher absorption or scattering.

Download or read book Novel Image Reconstruction Algorithm and System on Chip Design for Continuous wave Diffuse Optical Tomography Systems written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fiber Optic Sensor Prototype for Breast Cancer Imaging written by Adam Bangert and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Breast cancer is the most common type of cancer and the second most common cause of death by cancer for women. Early diagnosis of a malignant tumor in the breast can dramatically increase survivability. Therefore, the clarity and accuracy of a detection scheme is crucial to improve the survival rate of breast cancer. Near-Infrared Diffuse Optical Imaging and Spectroscopy (NIR-DOIS) is an imaging methodology under development which has the potential to clearly and accurately assess the malignancy of a suspicious lesion. Tumor malignancy corresponds to certain physiological parameters, namely oxygen saturation and hemoglobin concentration. NIR-DOIS is capable of measuring these parameters, providing a functional measurement of multiple physiological parameters with potential molecular sensitivity. When compared with other imaging modalities, NIR-DOIS has the advantage of being a low cost, non-invasive, real-time diagnostic. This imaging technique can be accomplished using fiber optic cables which are arrayed in a hand-held sensor head that is placed against the skin of the patient. The near-infrared light shines from the source fiber into the tissue and the reflected light is collected by the detector fibers. Source and detector fibers are connected to a tissue oximetry device that synchronizes the light illumination and the data collection, allowing it to interpret physiological parameters such as oxygen saturation and hemoglobin concentration from optical measurements. In order to reconstruct the embedded tissue heterogeneities such as breast tumors, it is necessary to collect multiple data sets with a matrix of sources and detectors. However, the fact that the existing tissue oximetry system has limited sources and detectors prevents the reconstruction of the tissue heterogeneities with high accuracy. In order to improve the imaging capability of the existing tissue oximetry system, it is necessary to develop an imaging head with a condensed distribution of source and detector channels, and an optical switching unit that can rapidly sweep through all these source and detector channels. The hypothesis of this project is that the optical switch will be an effective means to accurately detect oximetry data using NIR-DOIS. The research project includes completing a prototype optical switch, programming the necessary motor control functions to integrate the switch with a computer, and testing the device to determine baseline performance and potential clinical efficacy. Performance testing will be done using a laser and a light detector in order to determine light transmission through the optical switch, first through the fibers alone and then through the switch.

Download or read book Optical Tomography and Spectroscopy of Tissue VII written by Britton Chance and published by SPIE-International Society for Optical Engineering. This book was released on 2007 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theory/Algorithm/Modeling; Instrumentation and Technology I; Fluorescence Imaging/Spectroscopy (algorithm/model/tomography); Fluorescence Imaging/Image Reconstruction (Experimental); Instrumentation and Technology II; Fluorescence Imaging Technology I; Fluorescence Imaging Technology II; Fluorescence Imaging Technology III; Network for Translational Research in Optical Imaging: Breast Cancer Diffuse Optical Imaging; Breast II - Instrumentation & New Analysis Method; Breast III - Clinical Study; Pre-Clinical/Animal; Instrumentation and Technology III; Clinical/Human Subject Studies.

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 System Optimization and Iterative Image Reconstruction in Photoacoustic Computed Tomography for Breast Imaging written by Yang Lou (Biomedical engineer) and published by . This book was released on 2017 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photoacoustic computed tomography(PACT), also known as optoacoustic tomography (OAT), is an emerging imaging technique that has developed rapidly in recent years. The combination of the high optical contrast and the high acoustic resolution of this hybrid imaging technique makes it a promising candidate for human breast imaging, where conventional imaging techniques including X-ray mammography, B-mode ultrasound, and MRI suffer from low contrast, low specificity for certain breast types, and additional risks related to ionizing radiation. Though significant works have been done to push the frontier of PACT breast imaging, it is still challenging to successfully build a PACT breast imaging system and apply it to wide clinical use because of various practical reasons. First, computer simulation studies are often conducted to guide imaging system designs, but the numerical phantoms employed in most previous works consist of simple geometries and do not reflect the true anatomical structures within the breast. Therefore the effectiveness of such simulation-guided PACT system in clinical experiments will be compromised. Second, it is challenging to design a system to simultaneously illuminate the entire breast with limited laser power. Some heuristic designs have been proposed where the illumination is non-stationary during the imaging procedure, but the impact of employing such a design has not been carefully studied. Third, current PACT imaging systems are often optimized with respect to physical measures such as resolution or signal-to-noise ratio (SNR). It would be desirable to establish an assessing framework where the detectability of breast tumor can be directly quantified, therefore the images produced by such optimized imaging systems are not only visually appealing, but most informative in terms of the tumor detection task. Fourth, when imaging a large three-dimensional (3D) object such as the breast, iterative reconstruction algorithms are often utilized to alleviate the need to collect densely sampled measurement data hence a long scanning time. However, the heavy computation burden associated with iterative algorithms largely hinders its application in PACT breast imaging. This dissertation is dedicated to address these aforementioned problems in PACT breast imaging. A method that generates anatomically realistic numerical breast phantoms is first proposed to facilitate computer simulation studies in PACT. The non-stationary illumination designs for PACT breast imaging are then systematically investigated in terms of its impact on reconstructed images. We then apply signal detection theory to assess different system designs to demonstrate how an objective, task-based measure can be established for PACT breast imaging. To address theslow computation time of iterative algorithms for PACT imaging, we propose an acceleration method that employs an approximated but much faster adjoint operator during iterations, which can reduce the computation time by a factor of six without significantly compromising image quality. Finally, some clinical results are presented to demonstrate that the PACT breast imaging can resolve most major and fine vascular structures within the breast, along with some pathological biomarkers that may indicate tumor development.