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Evaluation of 10 current image reconstruction algorithms for linear array photoacoustic imaging

JOURNAL OF BIOPHOTONICS 2024年第3期17卷 e202300117-e202300117页

作者： Prakash, Ravi Manwar, Rayyan Avanaki, Kamran Univ Illinois Richard & Loan Hill Dept Biomed Engn Chicago IL 60607 USA Univ Illinois Dept Dermatol Chicago IL USA

Various reconstruction algorithms have been implemented for linear array photoacoustic imaging systems with the goal of accurately reconstructing the strength absorbers within the tissue being imaged. Since the existing algorithms have been introduced by different research groups and the context of performance evaluation was not consistent, it is difficult to make a fair comparison between them. In this study, we systematically compared the performance of 10 published image reconstruction algorithms (DAS, UBP, pDAS, DMAS, MV, EIGMV, SLSC, GSC, TR, and FD) using in-vitro phantom data. Evaluations were conducted based on lateral resolution of the reconstructed images, computational time, target detectability, and noise sensitivity. We anticipate the outcome of this study will assist researchers in selecting appropriate algorithms for their linear array PA imaging applications. Reconstructed photoacoustic images of blood-filled tubes in intralipid ***

关键词： image reconstruction algorithms linear array transducer photoacoustic imaging

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Towards Real-Time Three-Dimensional (3D) Imaging using Dynamic Metasurface Antennas 17

Towards Real-Time Three-Dimensional (3D) Imaging using Dynam...

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17th European Conference on Antennas and Propagation (EuCAP)

作者： Skouroliakou, Vasiliki Molaei, Amir Masoud Yurduseven, Okan Queens Univ Belfast Inst Elect Commun & Informat Technol ECIT Belfast BT3 9DT Antrim North Ireland

ISBN: (纸本)9788831299077

Dynamic Metasurface Antennas (DMAs) have been recently proposed as a computational imaging platform that relaxes the hardware constraints. These antennas produce tailored radiation patterns to multiplex the spatial information from the scene compressing the measurements into a single channel. Despite simplifying the hardware layer, the compression of the signal sets challenges in image reconstruction. The indirect sampling of the imaged scene makes it necessary to use computationally intense sensing-matrix based solutions since Fourier-based image reconstruction techniques are not directly applicable. In this paper, a bistatic case using DMAs as transmit and receive apertures is discussed and a pre-processing step is proposed to render the measurement set compatible with conventional Fourier-based imaging algorithms. The performance of the reconstruction algorithm including the pre-processing step is demonstrated when the algorithm is parallelized using a single Graphical Processing Unit (GPU) card arguing that real-time image reconstruction is possible when imaging with DMAs.

关键词： dynamic metasurface antennas microwave radar imaging three-dimensional imaging image reconstruction algorithms

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Electromagnetic Imaging for Breathing Monitoring

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SENSORS 2024年第23期24卷 7722页

作者： Vassilyev, Ivan Mendakulov, Zhassulan Special Design & Technol Bur Granit 292 Hussainov St Alma Ata 050060 Kazakhstan

The search for new non-invasive methods of investigating the functioning of human internal organs is an urgent task. One of these methods for assessing the functioning of the human respiratory system is electromagnetic sensing, which is based on a significant difference in the dielectric permittivity of muscle tissue and air. During breathing, when the lungs are filled with air, the dielectric permittivity of the lungs decreases, which leads to a change in the level of the electromagnetic signal passing through the body. The results of experiments on recording changes in the level of electromagnetic radiation passing through the human body performed on an experimental device consisting of eight transmitting and receiving antennas located on opposite sides of the chest have been presented in the article. The possibility of visualizing the measured "pulmonograms" in the form of dynamic two-dimensional images showing the process of filling various parts of the lungs with air has been demonstrated.

关键词： medical imaging image reconstruction algorithms electromagnetic sensors for physiological monitoring respiratory system disease localization microwave imaging techniques electromagnetic medical imaging and sensing (EMIS)

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High-Resolution Single-Pixel Imaging of Spatially Sparse Objects: Real-Time Imaging in the Near-Infrared and Visible Wavelength Ranges Enhanced with Iterative Processing or Deep Learning

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SENSORS 2024年第24期24卷 8139页

作者： Stojek, Rafal Pastuszczak, Anna Wrobel, Piotr Cwojdzinska, Magdalena Sobczak, Kacper Kotynski, Rafal Univ Warsaw Fac Phys Pasteura 5 PL-02 093 Warsaw Poland VIGO Photon Poznanska 129-133 PL-05850 Ozarow Mazowiecki Poland

We demonstrate high-resolution single-pixel imaging (SPI) in the visible and near-infrared wavelength ranges using an SPI framework that incorporates a novel, dedicated sampling scheme and a reconstruction algorithm optimized for the rapid imaging of highly sparse scenes at the native digital micromirror device (DMD) resolution of 1024 x 768. The reconstruction algorithm consists of two stages. In the first stage, the vector of SPI measurements is multiplied by the generalized inverse of the measurement matrix. In the second stage, we compare two reconstruction approaches: one based on an iterative algorithm and the other on a trained neural network. The neural network outperforms the iterative method when the object resembles the training set, though it lacks the generality of the iterative approach. For images captured at a compression of 0.41 percent, corresponding to a measurement rate of 6.8 Hz with a DMD operating at 22 kHz, the typical reconstruction time on a desktop with a medium-performance GPU is comparable to the image acquisition rate. This allows the proposed SPI method to support high-resolution dynamic SPI in a variety of applications, using a standard SPI architecture with a DMD modulator operating at its native resolution and bandwidth, and enabling the real-time processing of the measured data with no additional delay on a standard desktop PC.

关键词： single-pixel imaging infrared imaging compressive imaging computational imaging image reconstruction algorithms deep learning signal processing

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Quantification of Tomographic Incompleteness in Cone-Beam reconstruction

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IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2020年第1期4卷 63-80页

作者： Clackdoyle, Rolf Noo, Frederic CNRS TIMC IMAG Lab F-38700 Grenoble France Univ Utah Utah Ctr Adv Imaging Res Salt Lake City UT 84108 USA

For situations of cone-beam (CB) scanning where the measurements are incomplete, we propose a method to quantify the severity of the missing information at each voxel. This incompleteness metric is geometric;it uses only the relative locations of all CB vertices with respect to the voxel in question, and does not apply global information, such as the object extent or the pattern of incompleteness of other voxels. The values are non-negative, with zero indicating "least incompleteness," i.e., minimal danger of incompleteness artifacts. The incompleteness value can be related to the severity of the potential reconstruction artifact at the voxel location, independent of reconstruction algorithm. We performed a computer simulation of X-ray sources along a circular trajectory, and used small multidisk test-objects to examine the local effects of data incompleteness. The observed behavior of the reconstructed test-objects quantitatively matched the precalculated incompleteness values. A second simulation of a hypothetical SPECT breast imaging system used only 12 pinholes. reconstructions were performed using analytic and iterative methods, and five reconstructed test-objects matched the behavior predicted by the incompleteness model. The model is based on known sufficiency conditions for data incompleteness, and provides strong predictive guidance for what can go wrong with incomplete CB data.

关键词： Imaging image reconstruction algorithms tomography

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Identification of low energy nuclear recoils in a gas time projection chamber with optical readout

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MEASUREMENT SCIENCE AND TECHNOLOGY 2021年第2期32卷

作者： Baracchini, E. Benussi, L. Bianco, S. Capoccia, C. Caponero, M. Cavoto, G. Cortez, A. Costa, I. A. Di Marco, E. D'Imperio, G. Dho, G. Iacoangeli, F. Maccarrone, G. Marafini, M. Mazzitelli, G. Messina, A. Nobrega, R. A. Orlandi, A. Paoletti, E. Passamonti, L. Petrucci, F. Piccolo, D. Pierluigi, D. Pinci, D. Renga, F. Rosatelli, F. Russo, A. Saviano, G. Tesauro, R. Tomassini, S. Gran Sasso Sci Inst Laquila Italy Ist Nazl Fis Nucl Lab Nazl Gran Sasso Assergi Italy Ist Nazl Fis Nucl Lab Nazl Frascati Frascati Italy ENEA Ctr Ric Frascati Frascati Italy Ist Nazl Fis Nucl Sez Roma Rome Italy Sapienza Univ Roma Dipartimento Fis Rome Italy Univ Fed Juiz de Fora Juiz De Fora Brazil Museo Stor Fis Rome Italy Ctr Studi & Ric Enrico Fermi Rome Italy Univ Roma TRE Dipartimento Matemat & Fis Rome Italy Sapienza Univ Roma Dipartimento Ingn Chim Mat & Ambiente Rome Italy

The search for a novel technology, which is able to detect and reconstruct nuclear recoil events in the keV energy range, has become increasingly important now that vast regions of high mass weakly-interacting-massive-particle-like dark matter candidates have been excluded. Gaseous time projection chambers (TPC) with optical readout are very promising candidates combining the complete event information provided by the TPC technique with the high sensitivity and granularity of the latest generation light sensors. A TPC with an amplification at the anode, obtained with gas electron multipliers (GEMs), was tested at the Laboratori Nazionali di Frascati. Photons and neutrons from radioactive sources were employed to induce recoiling nuclei and electrons with kinetic energy in the range 1-100 keV. A He-CF4 (60/40) gas mixture was used at atmospheric pressure and the light produced during the multiplication in the GEM channels was acquired by a high-position resolution and low-noise complementary metal-oxide semiconductor camera and a photomultiplier. A multi-stage pattern recognition algorithm based on an advanced clustering technique is presented here. A number of cluster-shaped observables are used to identify nuclear recoils induced by neutrons, which originated from a AmBe source against x-ray Fe-55 photoelectrons. An efficiency of 18% to detect nuclear recoils with an energy of about 6 keV is reached, while suppressing 96% of the Fe-55 photoelectrons, making this optical read-out gas TPC a very promising candidate for future investigations of ultra-rare events such as directional direct dark matter searches.

关键词： instrumentation and detectors high-energy physics dark matter image reconstruction algorithms

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Sub-Nanosecond Cherenkov Photon Detection For Lhcb Particle Identification In High-Occupancy Conditions And Semiconductor Tracking For Muon Scattering Tomography

Sub-Nanosecond Cherenkov Photon Detection For Lhcb Particle ...

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作者： Floris Keizer University of Cambridge

学位级别：博士

The increase in luminosity during the LHC upgrade programme causes a challenging rise in track multiplicity and hit occupancy in the LHCb detector. In order to mitigate this effect, the use of photon detector hit time information is presented in the context of the Ring-Imaging Cherenkov (RICH) detectors. The application of a time gate in the FPGA of the digital readout board for the Upgrade Ia photon detector, which is being installed for LHC Run 3, is described. Data recorded during SPS charged particle beam tests using a 6.25 ns time gate show a reduction of up to a factor of four in asynchronous detector noise compared to the original 25ns readout. A time-walk correction based on the time-over- threshold is proposed. Using the LHCb simulation framework, the intrinsic time resolution of the RICH detectors is demonstrated to be less than 10 ps. This is particularly relevant for the LHCb Upgrade II, which is scheduled for the year 2030 in preparation for a further order- of-magnitude rise in luminosity. Methods of time gating and scaling of the signal amplitude in the RICH reconstruction likelihood maximisation algorithm are presented. The results show that, considering improvements in the time-resolution only, a photon detector with an approximately 50 ps resolution can achieve today's particle ID performance in the high- luminosity LHC environment. In the second part of this thesis, the first published semiconductor tracker for cosmic-ray muon scattering tomography is presented. The tracker uses silicon strip sensors from the ATLAS Semiconductor Tracker (SCT) with an 80μm pitch. A novel electronic readout system for the sensors is designed, based on a scalable, inexpensive, flexible, FPGA-based solution. A high-precision mechanical structure with integrated cooling is built to align the SCT modules. This alignment is fine-tuned in software, and the tracker performance is compared with a Geant4 simulation. A scattering angle resolution compatible with 1.5 mrad at t

关键词： CERN LHCb Single photon detection Cherenkov radiation Ring-imaging Cherenkov detectors Sub-nanosecond time resolution Particle detectors Silicon strip detectors Readout electronics Detector performance simulation Semiconductor tracker Cosmic radiation Muon scattering tomography image reconstruction algorithms Particle beam tests Photon sensors Detector cooling and alignment

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EVALUATION OF USEFULNESS OF DUAL-ENERGY COMPUTED TOMOGRAPHYS IN RADIOTHERAPY PLANNING FOR PATIENTS WITH HIP ENDOPROSTHESIS

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ACTA PHYSICA POLONICA B 2019年第3期50卷 349-360页

作者： Mazur, L. Kisielewicz, K. Dziecichowicz, A. Sapikowska, A. Maria Sklodowska Curie Mem Inst Oncol Ctr Oncol Krakow Branch Garncarska 11 PL-31115 Krakow Poland

Based on computed tomography (CT) scans of the interior of a patient's body, it is possible to precisely locate planning target volume (PTV) and organs at risk (OARs) for radiotherapy. Constant development of this kind of imaging techniques has led to the emergence of dual-energy CT, which in conjunction with Metal Artifact Reduction software (MARs) allows to restore the structures and compensate the disorders resulting from the presence of metallic implants in the patient's body. Such implants cause artifacts in the CT image which carries false information about the area between endoprosthesis. The aim of this thesis is evaluation of usefulness of dual-energy CT in radiotherapy planning for patients with hip endoprosthesis in comparison to manual method of reduction. This method relies heavily on estimating where a given tissue passes into another and inflicting one average HU (Hounsfield Units) value for the artifact site, based on the HU measurement for several neighboring tissues. Treatment plans were created using TPS (Treatment Planning System) Eclipse. Calculated dose distributions were imported into the Sun Nuclear application and subjected to gamma analysis. It can be concluded that the MARs algorithm is very useful for treatment planning, but it should be used with at most care.

关键词： DUAL energy CT (Tomography) FRAUD image reconstruction algorithms RADIOTHERAPY COMPUTED tomography CONTENT analysis

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image reconstruction for Electrical Impedance Tomography: Experimental Comparison of Radial Basis Neural Network and Gauss - Newton Method

Image Reconstruction for Electrical Impedance Tomography: Ex...

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15th IFAC/IEEE Conference on Programmable Devices and Embedded Systems (PDeS)

作者： Hrabuska, Radek Prauzek, Michal Venclikova, Marketa Konecny, Jaromir VSB Tech Univ Ostrava Dept Cybernet & Biomed Engn Ostrava 70833 Czech Republic

Electrical impedance tomography (EIT) is an intensively researched noninvasive diagnostic method for medical use, that can help to improve the lung diagnostics, artificial lung ventilation and prevent lung injuries. Further improvements of reconstruction algorithms and measurement devices are essential to widen the use of EIT as a lung diagnostic method. To test potential of Radial Basis Neural Networks (RBNN) and Hopfield Neural Networks (HNN) for image reconstruction experiment is carried. Said neural networks are compared with Gauss Newton (GN) algorithm. Results of the experiment show higher reconstruction accuracy with RBNN and HNN over GN algorithm. (C) 2018, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Electrical Impedance Tomography Neural Networks image reconstruction algorithms

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Repeatability and Reproducibility of Radiomic Features: A Systematic Review

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INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS 2018年第4期102卷 1143-1158页

作者： Traverso, Alberto Wee, Leonard Dekker, Andre Gillies, Robert MAASTRO Clin Dept Radiat Oncol Dr Tanslaan 12 NL-6229 ET Maastricht Netherlands Maastricht Univ Sch Oncol & Dev Biol GROW Maastricht Netherlands H Lee Moffitt Canc Ctr & Res Inst Tampa FL USA

Purpose: An ever-growing number of predictive models used to inform clinical decision making have included quantitative, computer-extracted imaging biomarkers, or "radiomic features." Broadly generalizable validity of radiomics-assisted models may be impeded by concerns about reproducibility. We offer a qualitative synthesis of 41 studies that specifically investigated the repeatability and reproducibility of radiomic features, derived from a systematic review of published peer-reviewed literature. Methods and Materials: The PubMed electronic database was searched using combinations of the broad Haynes and Ingui filters along with a set of text words specific to cancer, radiomics (including texture analyses), reproducibility, and repeatability. This review has been reported in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. From each full-text article, information was extracted regarding cancer type, class of radiomic feature examined, reporting quality of key processing steps, and statistical metric used to segregate stable features. Results: Among 624 unique records, 41 full-text articles were subjected to review. The studies primarily addressed non-small cell lung cancer and oropharyngeal cancer. Only 7 studies addressed in detail every methodologic aspect related to image acquisition, preprocessing, and feature extraction. The repeatability and reproducibility of radiomic features are sensitive at various degrees to processing details such as image acquisition settings, image reconstruction algorithm, digital image preprocessing, and software used to extract radiomic features. First-order features were overall more reproducible than shape metrics and textural features. Entropy was consistently reported as one of the most stable first-order features. There was no emergent consensus regarding either shape metrics or textural features;however, coarseness and contrast appeared among the least reproducible. Conclusions:

关键词： META-analysis BIOLOGICAL tags image reconstruction algorithms DIGITAL image processing ENTROPY

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