Optoacoustic tomography

  • Hybrid optical parametrically-oscillating emitter at 1930 nm for volumetric photoacoustic imaging of water content

    Hybrid optical parametrically-oscillating emitter at 1930 nm for volumetric photoacoustic imaging of water content

    eLight 2, 6 (2022) Jiawei Shi, Mingsheng Li, Huajun Tang, Jiqiang Kang, Najia Sharmin, Amir Rosenthal & Kenneth K. Y. Wong Abstract: Water plays a vital role in biological metabolism and it would be essential to trace the water content non-invasively, such as leveraging the vibrational absorption peak of the O–H bond. However, due to … Continue reading "Hybrid optical parametrically-oscillating emitter at 1930 nm for volumetric photoacoustic imaging of water content"Read More »
  • Silicon-photonics acoustic detector for optoacoustic micro-tomography.

    Silicon-photonics acoustic detector for optoacoustic micro-tomography.

    © 2022 Nature  Communications Technology developed at the Andrew and Erna Viterbi Faculty of Electrical and Computer Engineering will allow the miniaturization of ultrasound transducers, thereby improving their resolution New technology that allows for very high-resolution medical imaging (close to 10 ”m) is expected to lead to the development of tiny and effective ultrasound systems … Continue reading "Silicon-photonics acoustic detector for optoacoustic micro-tomography."Read More »
  • High-resolution silicon photonics focused ultrasound transducer with a sub-millimeter aperture.

    High-resolution silicon photonics focused ultrasound transducer with a sub-millimeter aperture.

    2023 Optics Letters Vol. 48, Issue 10, pp. 2668-2671 Michael Nagli, JĂŒrgen Koch, Yoav Hazan, Ahiad Levi, Orna Ternyak, Ludger Overmeyer, and Amir Rosenthal Abstract We present an all-optical focused ultrasound transducer with a sub-millimeter aperture and demonstrate its capability for high-resolution imaging of tissue ex vivo. The transducer is composed of a wideband silicon … Continue reading "High-resolution silicon photonics focused ultrasound transducer with a sub-millimeter aperture."Read More »
  • All-optical optoacoustic micro-tomography in reflection mode.

    All-optical optoacoustic micro-tomography in reflection mode.

    2023 Biomedical Engineering Letters Tamar Harary, Yoav Hazan & Amir Rosenthal Abstract High-resolution optoacoustic imaging at depths beyond the optical diffusion limit is conventionally performed using a microscopy setup where a strongly focused ultrasound transducer samples the image object point-by-point. Although recent advancements in miniaturized ultrasound detectors enables one to achieve microscopic resolution with an … Continue reading "All-optical optoacoustic micro-tomography in reflection mode."Read More »
  • Hand-Held Optoacoustic System for the Localization of Mid-Depth Blood Vessels.

    Hand-Held Optoacoustic System for the Localization of Mid-Depth Blood Vessels.

    Photonics 2022, 9(12), 907 Zohar Or,  Ahiad R.Levi,  Yoav Hazan and Amir Rosenthal Abstract The ability to rapidly locate blood vessels in patients is important in many clinical applications, e.g., in catheterization procedures. Optical techniques, including visual inspection, generally suffer from a reduced performance at depths below 1 mm, while ultrasound and optoacoustic tomography are … Continue reading "Hand-Held Optoacoustic System for the Localization of Mid-Depth Blood Vessels."Read More »
  • Miniaturized ultrasound detector arrays in silicon photonics using pulse transmission amplitude monitoring.

    Miniaturized ultrasound detector arrays in silicon photonics using pulse transmission amplitude monitoring.

    © 2022 Optica Publishing Group  Yoav Hazan, Michael Nagli, Ahiad Levi, and Amir Rosenthal Abstract Silicon photonics holds promise for a new generation of ultrasound-detection technology, based on optical resonators, with unparalleled miniaturization levels, sensitivities, and bandwidths, creating new possibilities for minimally invasive medical devices. While existing fabrication technologies are capable of producing dense resonator … Continue reading "Miniaturized ultrasound detector arrays in silicon photonics using pulse transmission amplitude monitoring."Read More »
  • Single-detector 3D optoacoustic tomography via coded spatial acoustic modulation.

    Single-detector 3D optoacoustic tomography via coded spatial acoustic modulation.

    2022 Communications Engineering Evgeny Hahamovich, Sagi Monin, Ahiad Levi, Yoav Hazan & Amir Rosenthal Abstract Optoacoustic tomography (OAT) is a hybrid imaging modality that combines optical excitation with ultrasound detection and enables high-resolution visualization of optical contrasts at tissue depths in which light is completely diffused. Despite its promise in numerous research and clinical applications, … Continue reading "Single-detector 3D optoacoustic tomography via coded spatial acoustic modulation."Read More »
  • GrĂŒneisen-relaxation photoacoustic microscopy at 1.7 ”m and its application in lipid imaging.

    GrĂŒneisen-relaxation photoacoustic microscopy at 1.7 ”m and its application in lipid imaging.

    © 2020 Optical Society of America AbstractWe report the first, to the best of our knowledge, demonstration of GrĂŒneisen relaxation photoacoustic microscopy (GR-PAM) of lipid-rich tissue imaging at the 1.7 ”m band, implemented with a high-energy thulium-doped fiber laser and a fiber-based delay line. GR-PAM enhances the image contrast by intensifying the region of strong … Continue reading "GrĂŒneisen-relaxation photoacoustic microscopy at 1.7 ”m and its application in lipid imaging."Read More »
  • Increased SNR in acousto-optic imaging via coded ultrasound transmission.

    Increased SNR in acousto-optic imaging via coded ultrasound transmission.

    © 2020 Optical Society of America Abstract Acousto-optic imaging (AOI) is a non-invasive method that uses acoustic modulation to map the light fluence inside biological tissue. In many AOI implementations, ultrasound pulses are used in a time-gated measurement to perform depth-resolved imaging without the need for mechanical scanning. However, to achieve high axial resolution, it … Continue reading "Increased SNR in acousto-optic imaging via coded ultrasound transmission."Read More »
  • Ultrasound Detection Arrays Via Coded Hadamard Apertures.

    Ultrasound Detection Arrays Via Coded Hadamard Apertures.

    © 2020 IEEE AbstractIn the medical fields, ultrasound detection is often performed with piezoelectric arrays that enable one to simultaneously map the acoustic fields at several positions. In this work, we develop a novel method for transforming a single-element ultrasound detector into an effective detectionarray by spatially filtering the incoming acoustic fields using a binary … Continue reading "Ultrasound Detection Arrays Via Coded Hadamard Apertures."Read More »
  • The Impulse Response of Negatively Focused Spherical Ultrasound Detectors and its Effect on Tomographic Optoacoustic Reconstruction.

    The Impulse Response of Negatively Focused Spherical Ultrasound Detectors and its Effect on Tomographic Optoacoustic Reconstruction.

    source: © 2019  IEEE Transactions on Medical Imaging.  In optoacoustic tomography, negatively focused detectors have been shown to improve the tangential image resolution without sacrificing sensitivity. Since no exact inversion formulae exist for optoacoustic image reconstruction with negatively focused detectors, image reconstruction in such cases is based on using the virtual-detector approximation, in which it … Continue reading "The Impulse Response of Negatively Focused Spherical Ultrasound Detectors and its Effect on Tomographic Optoacoustic Reconstruction."Read More »
  • Algebraic determination of back-projection operators for optoacoustic tomography

    Algebraic determination of back-projection operators for optoacoustic tomography

    source: © 2018 Optical Society of America The simplicity and computational efficiency of back-projection formulae have made them a popular choice in optoacoustic tomography. Nonetheless, exact back-projection formulae exist for only a small set of tomographic problems. This limitation is overcome by algebraic algorithms, but at the cost of higher numerical complexity. In this paper, … Continue reading "Algebraic determination of back-projection operators for optoacoustic tomography"Read More »
  • Analysis of Negatively Focused Ultrasound Detectors in Optoacoustic Tomography

    Analysis of Negatively Focused Ultrasound Detectors in Optoacoustic Tomography

    source:© 2017 IEEE Transactions on Medical Imaging In optoacoustic tomography, negatively focused transducers may be used for improving the tangential image resolution while preserving a high signal-to-noise ratio. Commonly, image reconstruction in such scenarios is facilitated by the use of the virtual-detector approach. Although the validity of this approach has been experimentally verified, it is … Continue reading "Analysis of Negatively Focused Ultrasound Detectors in Optoacoustic Tomography"Read More »
  • Optoacoustic image reconstruction and system analysis for finite-aperture detectors under the wavelet-packet framework.

    Optoacoustic image reconstruction and system analysis for finite-aperture detectors under the wavelet-packet framework.

    source: © 2016 J. of Biomedical Optics In optoacoustic tomography, detectors with relatively large areas are often employed to achieve high detection sensitivity. However, spatial-averaging effects over large detector areas may lead to attenuation of high acoustic frequencies and, subsequently, loss of fine features in the reconstructed image. Model-based reconstruction algorithms improve image resolution in such … Continue reading "Optoacoustic image reconstruction and system analysis for finite-aperture detectors under the wavelet-packet framework."Read More »
  • High-Throughput Sparsity-Based Inversion Scheme for Optoacoustic Tomography

    High-Throughput Sparsity-Based Inversion Scheme for Optoacoustic Tomography

    source: © 2016 IEEE Transactions on Medical Imaging The concept of sparsity is extensively exploited in the fields of data acquisition and image processing, contributing to better signal-to-noise and spatio-temporal performance of the various imaging methods. In the field of optoacoustic tomography, the image reconstruction problem is often characterized by computationally extensive inversion of very large … Continue reading "High-Throughput Sparsity-Based Inversion Scheme for Optoacoustic Tomography"Read More »
  • Optical and optoacoustic model-based tomography: theory and current challenges for deep tissue imaging of optical contrast

    Optical and optoacoustic model-based tomography: theory and current challenges for deep tissue imaging of optical contrast

    source:© 2015 IEEE Signal Processing Magazine Light offers a range of interactions with tissue that give rise to an extensive list of methods to sense physical, chemical, or biological processes. Combined with using safe and nonionizing radiation, optical imaging is considered as a fundamental tool in the biomedical sciences.[Read More…]ï»ż Fig. 1 Principles of optical … Continue reading "Optical and optoacoustic model-based tomography: theory and current challenges for deep tissue imaging of optical contrast"Read More »
  • Sparsity‐based acoustic inversion in cross‐sectional multiscale optoacoustic imaging.

    Sparsity‐based acoustic inversion in cross‐sectional multiscale optoacoustic imaging.

    source: © 2015  Medical physics & American Association of Physicists in Medicine Purpose:With recent advancement in hardware of optoacoustic imaging systems, highly detailed cross‐sectional images may be acquired at a single laser shot, thus eliminating motion artifacts. Nonetheless, other sources of artifacts remain due to signal distortion or out‐of‐plane signals. The purpose of image reconstruction algorithms … Continue reading "Sparsity‐based acoustic inversion in cross‐sectional multiscale optoacoustic imaging."Read More »