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La TA, Ülgen O, Shnaiderman R, Ntziachristos V. Bragg grating etalon-based optical fiber for ultrasound and optoacoustic detection. Nat Commun 2024; 15:7521. [PMID: 39214964 PMCID: PMC11364814 DOI: 10.1038/s41467-024-51497-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Accepted: 08/09/2024] [Indexed: 09/04/2024] Open
Abstract
Fiber-based interferometers receive significant interest as they lead to miniaturization of optoacoustic and ultrasound detectors without the quadratic loss of sensitivity common to piezoelectric elements. Nevertheless, in contrast to piezoelectric crystals, current fiber-based ultrasound detectors operate with narrow ultrasound bandwidth which limits the application range and spatial resolution achieved in imaging implementations. We port the concept of silicon waveguide etalon detection to optical fibers using a sub-acoustic reflection terminator to a Bragg grating embedded etalon resonator (EER), uniquely implementing direct and forward-looking access to incoming ultrasound waves. Precise fabrication of the terminator is achieved by continuously recording the EER spectrum during polishing and fitting the spectra to a theoretically calculated spectrum for the selected thickness. Characterization of the EER inventive design reveals a small aperture (10.1 µm) and an ultra-wide bandwidth (160 MHz) that outperforms other fiber resonators and enables an active detection area and overall form factor that is smaller by more than an order of magnitude over designs based on piezoelectric transducers. We discuss how the EER paves the way for the most adept fiber-based miniaturized sound detection today, circumventing the limitations of currently available designs.
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Affiliation(s)
- Tai Anh La
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Okan Ülgen
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Rami Shnaiderman
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine and Health, Technical University of Munich, Munich, Germany
| | - Vasilis Ntziachristos
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany.
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine and Health, Technical University of Munich, Munich, Germany.
- Munich Institute of Biomedical Engineering (MIBE), Technical University of Munich, Garching b. München, Germany.
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2
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Yang S, Hu S. Perspectives on endoscopic functional photoacoustic microscopy. APPLIED PHYSICS LETTERS 2024; 125:030502. [PMID: 39022117 PMCID: PMC11251735 DOI: 10.1063/5.0201691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 06/27/2024] [Indexed: 07/20/2024]
Abstract
Endoscopy, enabling high-resolution imaging of deep tissues and internal organs, plays an important role in basic research and clinical practice. Recent advances in photoacoustic microscopy (PAM), demonstrating excellent capabilities in high-resolution functional imaging, have sparked significant interest in its integration into the field of endoscopy. However, there are challenges in achieving functional PAM in the endoscopic setting. This Perspective article discusses current progress in the development of endoscopic PAM and the challenges related to functional measurements. Then, it points out potential directions to advance endoscopic PAM for functional imaging by leveraging fiber optics, microfabrication, optical engineering, and computational approaches. Finally, it highlights emerging opportunities for functional endoscopic PAM in basic and translational biomedicine.
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Affiliation(s)
- Shuo Yang
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Song Hu
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
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3
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Cao X, Yang H, Wu ZL, Li BB. Ultrasound sensing with optical microcavities. LIGHT, SCIENCE & APPLICATIONS 2024; 13:159. [PMID: 38982066 PMCID: PMC11233744 DOI: 10.1038/s41377-024-01480-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/10/2024] [Accepted: 05/13/2024] [Indexed: 07/11/2024]
Abstract
Ultrasound sensors play an important role in biomedical imaging, industrial nondestructive inspection, etc. Traditional ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized, with typical sizes at the millimeter to centimeter scale. To overcome these challenges, optical ultrasound sensors have emerged as a promising alternative, offering both high sensitivity and spatial resolution. In particular, ultrasound sensors utilizing high-quality factor (Q) optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth, while also enabling mass production on silicon chips. In this review, we focus on recent advances in ultrasound sensing applications using three types of optical microcavities: Fabry-Perot cavities, π-phase-shifted Bragg gratings, and whispering gallery mode microcavities. We provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound sensors. Furthermore, we survey recent advances in ultrasound sensing using these microcavity-based approaches, highlighting their applications in diverse detection scenarios, such as photoacoustic imaging, ranging, and particle detection. The goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.
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Affiliation(s)
- Xuening Cao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hao Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zu-Lei Wu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Bei-Bei Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China.
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4
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Kaffas AE, Vo-Phamhi JM, Griffin JF, Hoyt K. Critical Advances for Democratizing Ultrasound Diagnostics in Human and Veterinary Medicine. Annu Rev Biomed Eng 2024; 26:49-65. [PMID: 38166185 PMCID: PMC11238906 DOI: 10.1146/annurev-bioeng-110222-095229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
The democratization of ultrasound imaging refers to the process of making ultrasound technology more accessible. Traditionally, ultrasound imaging has been predominately used in specialized medical facilities by trained professionals. Advancements in technology and changes in the health-care landscape have inspired efforts to broaden the availability of ultrasound imaging to various settings such as remote and resource-limited areas. In this review, we highlight several key factors that have contributed to the ongoing democratization of ultrasound imaging, including portable and handheld devices, recent advancements in technology, and training and education. Examples of diagnostic point-of-care ultrasound (POCUS) imaging used in emergency and critical care, gastroenterology, musculoskeletal applications, and other practices are provided for both human and veterinary medicine. Open challenges and the future of POCUS imaging are presented, including the emerging role of artificial intelligence in technology development.
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Affiliation(s)
- Ahmed El Kaffas
- Department of Radiology, School of Medicine, Stanford University, Stanford, California, USA
| | - Jenny M Vo-Phamhi
- Department of Radiology, School of Medicine, Stanford University, Stanford, California, USA
| | - John F Griffin
- Department of Large Animal Clinical Sciences, Texas A&M University, College Station, Texas, USA
| | - Kenneth Hoyt
- Department of Small Animal Clinical Sciences, Texas A&M University, College Station, Texas, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas, USA;
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5
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Song W, Zhuang Y, Yang Y, Xie D, Min C, Yuan X. Speckle Variance Photoacoustic Microscopy for Microhemodynamic Imaging. ACS Sens 2024; 9:2166-2175. [PMID: 38625680 DOI: 10.1021/acssensors.4c00292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Relying on the strong optical absorption of hemoglobin to pulsed laser energy, photoacoustic microscopy provides morphological and functional information on microvasculature label-freely. Here, we propose speckle variance photoacoustic microscopy (SV-PAM), which harnesses intrinsic imaging contrast from temporal-varied photoacoustic signals of moving red blood cells in blood vessels, for recovering three-dimension hemodynamic images down to capillary-level resolution within the microcirculatory tissue beds in vivo. Calculating the speckle variance of consecutive photoacoustic B-scan frames acquired at the same lateral position enables accurate identification of blood perfusion and occlusion, which provides interpretations of dynamic blood flow in the microvasculature, in addition to the microvascular anatomic structures. We demonstrate high-resolution hemodynamic imaging of vascular occlusion and reperfusion in the microvasculature of mice ears in vivo. The results suggest that our SV-PAM is potentially invaluable for biomedical hemodynamic investigations, for example, imaging ischemic stroke and hemorrhagic stroke.
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Affiliation(s)
- Wei Song
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yiyan Zhuang
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yifan Yang
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Deyan Xie
- School of Science and Information Science, Qingdao Agricultural University, Qingdao 266109, China
| | - Changjun Min
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Xiaocong Yuan
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
- Research Center for Frontier Fundamental Studies, Zhejiang Laboratory, Hangzhou 311100, China
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6
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Hosseindokht Z, Davoudi S, Rahdar M, Janahmadi M, Kolahdouz M, Sasanpoour P. Photoacoustic viscoelasticity assessment of prefrontal cortex and cerebellum in normal and prenatal valproic acid-exposed rats. PHOTOACOUSTICS 2024; 36:100590. [PMID: 38318427 PMCID: PMC10839762 DOI: 10.1016/j.pacs.2024.100590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/11/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024]
Abstract
Mechanical properties of brain tissues are from principal features from different points of view; diagnosis, the performance of the brain and neurological disorders. Particularly viscoelastic properties of the brain tissues are determinative. In this study based on a proposed accurate and non-invasive method, we have measured the viscoelastic properties of prefrontal cortex and cerebellum, two important brain regions involved in motor learning and pathophysiology of autism spectrum disorder (ASD). In this regard, using photoacoustic systems, viscoelastic properties of tissues from the cerebellum and prefrontal cortex of normal and prenatal VPA (Valproic acid)-exposed (i.e. autistic-like) offspring rats are measured. Results of our study show that the cerebellums of normal tissues are stiffer than the tissue obtained from autistic-like rats, while the viscoelasticity of the prefrontal cortex of normal tissues is higher than that of autistic ones. The proposed method for the measurement of viscoelastic properties of the brain tissue has the potential not only for the fundamental studies but as a diagnosis technique.
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Affiliation(s)
- Zahra Hosseindokht
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Shima Davoudi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mona Rahdar
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahyar Janahmadi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammadreza Kolahdouz
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Pezhman Sasanpoour
- Department of Medical Physics and Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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7
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Zhu L, Cao H, Ma J, Wang L. Optical ultrasound sensors for photoacoustic imaging: a review. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:S11523. [PMID: 38303991 PMCID: PMC10831871 DOI: 10.1117/1.jbo.29.s1.s11523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 01/08/2024] [Accepted: 01/10/2024] [Indexed: 02/03/2024]
Abstract
Significance Photoacoustic (PA) imaging is an emerging biomedical imaging modality that can map optical absorption contrast in biological tissues by detecting ultrasound signal. Piezoelectric transducers are commonly used in PA imaging to detect the ultrasound signals. However, piezoelectric transducers suffer from low sensitivity when the dimensions are reduced and are easily influenced by electromagnetic interference. To avoid these limitations, various optical ultrasound sensors have been developed and shown their great potential in PA imaging. Aim Our study aims to summarize recent progress in optical ultrasound sensor technologies and their applications in PA imaging. Approach The commonly used optical ultrasound sensing techniques and their applications in PA systems are reviewed. The technical advances of different optical ultrasound sensors are summarized. Results Optical ultrasound sensors can provide wide bandwidth and improved sensitivity with miniatured size, which enables their applications in PA imaging. Conclusions The optical ultrasound sensors are promising transducers in PA imaging to provide higher-resolution images and can be used in new applications with their unique advantages.
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Affiliation(s)
- Liying Zhu
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
| | - Hongming Cao
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
| | - Jun Ma
- Nanfang Hospital, Southern Medical University, Department of Burns, Guangzhou, China
| | - Lidai Wang
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
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8
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Lee Y, Rong Q, Song KH, Czaplewski DA, Zhang HF, Yao J, Sun C. Theoretical and experimental study on the detection limit of the micro-ring resonator based ultrasound point detectors. PHOTOACOUSTICS 2023; 34:100574. [PMID: 38126078 PMCID: PMC10731384 DOI: 10.1016/j.pacs.2023.100574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/06/2023] [Accepted: 11/21/2023] [Indexed: 12/23/2023]
Abstract
Combining the diffusive laser excitation and the photoacoustic signals detection, photoacoustic computed tomography (PACT) is uniquely suited for deep tissue imaging. A diffraction-limited ultrasound point detector is highly desirable for maximizing the spatial resolution and the field-of-view of the reconstructed volumetric images. Among all the available ultrasound detectors, micro-ring resonator (MRR) based ultrasound detectors offer the lowest area-normalized limit of detection (nLOD) in a miniature form-factor, making it an ideal candidate as an ultrasound point detector. However, despite their wide adoption for photoacoustic imaging, the underlying signal transduction process has not been systematically studied yet. Here we report a comprehensive theoretical model capturing the transduction of incident acoustic signals into digital data, and the associated noise propagation process, using experimentally calibrated key process parameters. The theoretical model quantifies the signal-to-noise ratio (SNR) and the nLOD under the influence of the key process variables, including the quality factor (Q-factor) of the MRR and the driving wavelength. While asserting the need for higher Q-factors, the theoretical model further quantifies the optimal driving wavelength for optimizing the nLOD. Given the MRR with a Q-factor of 1 × 105, the theoretical model predicts an optimal SNR of 30.1 dB and a corresponding nLOD of 3.75 × 10-2 mPa mm2/Hz1/2, which are in good agreement with the experimental measurements of 31.0 dB and 3.39 × 10-2 mPa mm2/Hz1/2, respectively. The reported theoretical model can be used in guiding the optimization of MRR-based ultrasonic detectors and PA experimental conditions, in attaining higher imaging resolution and contrast. The optimized operating condition has been further validated by performing PACT imaging of a human hair phantom.
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Affiliation(s)
- Youngseop Lee
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Qiangzhou Rong
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Ki-Hee Song
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - David A Czaplewski
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Junjie Yao
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Cheng Sun
- Department of Mechanical Engineering, Northwestern University, Evanston IL 60208, USA
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9
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Howe GA, Tang MX, Rowlands CJ. Tailored photoacoustic apertures with superimposed optical holograms. BIOMEDICAL OPTICS EXPRESS 2023; 14:6361-6380. [PMID: 38420325 PMCID: PMC10898579 DOI: 10.1364/boe.507453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 03/02/2024]
Abstract
A new method of generating potentially arbitrary photoacoustic wavefronts with optical holograms is presented. This method uses nanosecond laser pulses at 1064 nm that are split into four time-delayed components by means of a configurable multipass optical delay apparatus, which serves to map the pulses onto phase-delayed regions of a given acoustic wavefront. A single spatial light modulator generates separate holograms for each component, which are imaged onto a photoacoustic transducer comprised of a thermoelastic polymer. As a proof of concept of the broader arbitrary wavefront construction technique, the spatially- and temporally-modulated holograms in this study produce a phased array effect that enables beam steering of the resulting acoustic pulse. For a first experimental demonstration of the method, as verified by simulation, the acoustic beam is steered in four directions by around 5 degrees.
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Affiliation(s)
- Glenn A Howe
- Department of Bioengineering, Imperial College London, Royal School of Mines, Prince Consort Road, London, SW7 2BX, UK
| | - Meng-Xing Tang
- Department of Bioengineering, Imperial College London, Royal School of Mines, Prince Consort Road, London, SW7 2BX, UK
| | - Christopher J Rowlands
- Department of Bioengineering, Imperial College London, Royal School of Mines, Prince Consort Road, London, SW7 2BX, UK
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10
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Setia A, Mehata AK, Priya V, Pawde DM, Jain D, Mahto SK, Muthu MS. Current Advances in Nanotheranostics for Molecular Imaging and Therapy of Cardiovascular Disorders. Mol Pharm 2023; 20:4922-4941. [PMID: 37699355 DOI: 10.1021/acs.molpharmaceut.3c00582] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Cardiovascular diseases (CVDs) refer to a collection of conditions characterized by abnormalities in the cardiovascular system. They are a global problem and one of the leading causes of mortality and disability. Nanotheranostics implies to the combination of diagnostic and therapeutic capabilities inside a single nanoscale platform that has allowed for significant advancement in cardiovascular diagnosis and therapy. These advancements are being developed to improve imaging capabilities, introduce personalized therapies, and boost cardiovascular disease patient treatment outcomes. Significant progress has been achieved in the integration of imaging and therapeutic capabilities within nanocarriers. In the case of cardiovascular disease, nanoparticles provide targeted delivery of therapeutics, genetic material, photothermal, and imaging agents. Directing and monitoring the movement of these therapeutic nanoparticles may be done with pinpoint accuracy by using imaging modalities such as cardiovascular magnetic resonance (CMR), computed tomography (CT), positron emission tomography (PET), photoacoustic/ultrasound, and fluorescence imaging. Recently, there has been an increasing demand of noninvasive for multimodal nanotheranostic platforms. In these platforms, various imaging technologies such as optical and magnetic resonance are integrated into a single nanoparticle. This platform helps in acquiring more accurate descriptions of cardiovascular diseases and provides clues for accurate diagnosis. Advances in surface functionalization methods have strengthened the potential application of nanotheranostics in cardiovascular diagnosis and therapy. In this Review, we have covered the potential impact of nanomedicine on CVDs. Additionally, we have discussed the recently developed various nanoparticles for CVDs imaging. Moreover, advancements in the CMR, CT, PET, ultrasound, and photoacoustic imaging for the CVDs have been discussed. We have limited our discussion to nanomaterials based clinical trials for CVDs and their patents.
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Affiliation(s)
- Aseem Setia
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Abhishesh Kumar Mehata
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Vishnu Priya
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Datta Maroti Pawde
- School of Pharmacy & Technology Management, SVKM's Narsee Monjee Institute of Management Studies (NMIMS) Deemed-to-be University, Shirpur, Dhule, Maharashtra 425405, India
| | - Dharmendra Jain
- Department of Cardiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
| | - Sanjeev Kumar Mahto
- School of Biomedical Engineering, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Madaswamy S Muthu
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
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11
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Zhang J, Long X, Zhang G, Ma Z, Li W, Wang Y, Yang F, Lin R, Li C, Lam KH. Broadband transparent ultrasound transducer with polymethyl methacrylate as matching layer for in vivo photoacoustic microscopy. PHOTOACOUSTICS 2023; 33:100548. [PMID: 38021293 PMCID: PMC10658616 DOI: 10.1016/j.pacs.2023.100548] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/20/2023] [Accepted: 08/22/2023] [Indexed: 12/01/2023]
Abstract
Photoacoustic imaging (PAI) uniquely combines optics and ultrasound, presenting a promising role in biomedical imaging as a non-invasive and label-free imaging technology. As the traditional opaque ultrasound (US) transducers could hinder the transportation of the excitation light and limit the performance of PAI system, piezoelectric transparent ultrasonic transducers (TUTs) with indium tin oxide (ITO) electrodes have been developed to allow light transmission through the transducer and illuminate the sample directly. Nevertheless, without having transparent matching materials with appropriate properties, the bandwidth of those TUTs was generally narrow. In this work, we propose to employ polymethyl methacrylate (PMMA) as the matching layer material to improve the bandwidth of lithium niobate (LN)-based TUTs. The effects of PMMA matching layer on the performance of TUTs have been systematically studied. With the optimized PMMA matching layer, the very wide bandwidth of > 50 % could be achieved for the TUTs even with different transducer frequencies, leading to the great enhancement of axial resolution when compared to the similar reported work. In addition, the imaging performance of the developed TUT prototype has been evaluated in a PAI system and demonstrated by both phantom and in vivo small animal imaging.
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Affiliation(s)
- Jiaming Zhang
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Xing Long
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
| | - Guangjie Zhang
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
| | - Zhongtian Ma
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
| | - Wenzhao Li
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
| | - Yibing Wang
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
| | - Fan Yang
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Riqiang Lin
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Changhui Li
- Department of Biomedical Engineering, College of Future Technology, Peking University, Beijing 100871, China
- National Biomedical Imaging Center, Peking University, Beijing 100871, China
| | - Kwok-Ho Lam
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Medical and Industrial Ultrasonics, James Watt School of Engineering, University of Glasgow, Glasgow, Scotland, UK
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12
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Nagli M, Moisseev R, Suleymanov N, Kaminski E, Hazan Y, Gelbert G, Goykhman I, Rosenthal A. Silicon photonic acoustic detector (SPADE) using a silicon nitride microring resonator. PHOTOACOUSTICS 2023; 32:100527. [PMID: 37645254 PMCID: PMC10461202 DOI: 10.1016/j.pacs.2023.100527] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/14/2023] [Accepted: 06/30/2023] [Indexed: 08/31/2023]
Abstract
Silicon photonics is an emerging platform for acoustic sensing, offering exceptional miniaturization and sensitivity. While efforts have focused on silicon-based resonators, silicon nitride resonators can potentially achieve higher Q-factors, further enhancing sensitivity. In this work, a 30 µm silicon nitride microring resonator was fabricated and coated with an elastomer to optimize acoustic sensitivity and signal fidelity. The resonator was characterized acoustically, and its capability for optoacoustic tomography was demonstrated. An acoustic bandwidth of 120 MHz and a noise-equivalent pressure of ∼ 7 mPa/Hz1/2 were demonstrated. The spatially dependent impulse response agreed with theoretical predictions, and spurious acoustic signals, such as reverberations and surface acoustic waves, had a marginal impact. High image fidelity optoacoustic tomography of a 20 µm knot was achieved, confirming the detector's imaging capabilities. The results show that silicon nitride offers low signal distortion and high-resolution optoacoustic imaging, proving its versatility for acoustic imaging applications.
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Affiliation(s)
- Michael Nagli
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Ron Moisseev
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Nathan Suleymanov
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Eitan Kaminski
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Yoav Hazan
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Gil Gelbert
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Ilya Goykhman
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
| | - Amir Rosenthal
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion – Israel Institute of Technology, Technion City 32000, Haifa, Israel
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13
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Lee Y, Zhang HF, Sun C. Highly sensitive ultrasound detection using nanofabricated polymer micro-ring resonators. NANO CONVERGENCE 2023; 10:30. [PMID: 37338745 DOI: 10.1186/s40580-023-00378-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 06/01/2023] [Indexed: 06/21/2023]
Abstract
Photoacoustic (PA) imaging enables noninvasive volumetric imaging of biological tissues by capturing the endogenous optical absorption contrast. Conventional ultrasound detectors using piezoelectric materials have been widely used for transducing ultrasound signals into the electrical signals for PA imaging reconstruction. However, their inherent limitations in detection bandwidth and sensitivity per unit area have unfortunately constrained the performance of PA imaging. Optical based ultrasound detection methods emerge to offer very promising solutions. In particular, polymer micro-ring resonators (MRRs) in the form of integrated photonic circuits (IPC) enable significant reduction for the sensing area to 80 μm in diameter, while maintaining highly sensitive ultrasound detection with noise equivalent pressure (NEP) of 0.49 Pa and a broad detection frequency range up to 250 MHz. The continued engineering innovation has further transformed MRRs to be transparent to the light and thus, opens up a wide range of applications, including multi-modality optical microscope with isometric resolution, PA endoscope, photoacoustic computed tomography (PACT), and more. This review article summarizes and discusses the evolution of polymer MRR design and the associated nanofabrication process for improving the performance of ultrasound detection. The resulting novel imaging applications will also be reviewed and discussed.
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Affiliation(s)
- Youngseop Lee
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Cheng Sun
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, 60208, USA.
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Pan J, Li Q, Feng Y, Zhong R, Fu Z, Yang S, Sun W, Zhang B, Sui Q, Chen J, Shen Y, Li Z. Parallel interrogation of the chalcogenide-based micro-ring sensor array for photoacoustic tomography. Nat Commun 2023; 14:3250. [PMID: 37277353 DOI: 10.1038/s41467-023-39075-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 05/25/2023] [Indexed: 06/07/2023] Open
Abstract
Photoacoustic tomography (PAT), also known as optoacoustic tomography, is an attractive imaging modality that provides optical contrast with acoustic resolutions. Recent progress in the applications of PAT largely relies on the development and employment of ultrasound sensor arrays with many elements. Although on-chip optical ultrasound sensors have been demonstrated with high sensitivity, large bandwidth, and small size, PAT with on-chip optical ultrasound sensor arrays is rarely reported. In this work, we demonstrate PAT with a chalcogenide-based micro-ring sensor array containing 15 elements, while each element supports a bandwidth of 175 MHz (-6 dB) and a noise-equivalent pressure of 2.2 mPaHz-1/2. Moreover, by synthesizing a digital optical frequency comb (DOFC), we further develop an effective means of parallel interrogation to this sensor array. As a proof of concept, parallel interrogation with only one light source and one photoreceiver is demonstrated for PAT with this sensor array, providing images of fast-moving objects, leaf veins, and live zebrafish. The superior performance of the chalcogenide-based micro-ring sensor array and the effectiveness of the DOFC-enabled parallel interrogation offer great prospects for advancing applications in PAT.
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Affiliation(s)
- Jingshun Pan
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China
- Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices, South China Normal University, Guangzhou, 510006, China
| | - Qiang Li
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yaoming Feng
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Ruifeng Zhong
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhihao Fu
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Shuixian Yang
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Weiyuan Sun
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Bin Zhang
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China
| | - Qi Sui
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China
| | - Jun Chen
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yuecheng Shen
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China.
| | - Zhaohui Li
- School of Electronics and Information Technology, Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems, Sun Yat-sen University, Guangzhou, 510275, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China.
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Gadallah MT, Mohamed AEA, Hefnawy A, Zidan H, El-banby G, Badawy SM. A Mathematical Model for Simulating Photoacoustic Signal Generation Process in Biological Tissues.. [DOI: 10.21203/rs.3.rs-2928563/v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Background: Biomedical photoacoustic imaging (PAI) is a hybrid imaging modality based on the laser-generated ultrasound waves due to the photoacoustic (PA) effect physical phenomenon that has been reported firstly by A. G. Bell in 1880. Numerical modeling-based simulation for the PA signal generation process in biological tissues helps researchers for decreasing error trials in-vitro and hence decreasing error rates for in-vivo experiments. Numerical modeling methods help in obtaining a rapid modeling procedure comparable to pure mathematics. However, if a proper simplified mathematical model can be founded before applying numerical modeling techniques, it will be a great advantage for the overall numerical model. Most scientific theories, equations, and assumptions, been proposed to mathematically model the complete PA signal generation and propagation process in biological tissues, are so complicated. Hence, the researchers, especially the beginners, will find a hard difficulty to explore and obtain a proper simplified mathematical model describing the process. That’s why this paper is introduced.
Methods: In this paper we have tried to simplify understanding for the biomedical PA wave’s generation and propagation process, deducing a simplified mathematical model for the whole process. The proposed deduced model is based on three steps: a- pulsed laser irradiance, b- diffusion of light through biological tissue, and c- acoustic pressure wave generation and propagation from the target tissue to the ultrasound transducer surface. COMSOL Multiphysics, which is founded due to the finite element method (FEM) numerical modeling principle, has been utilized to validate the proposed deduced mathematical model on a simulated biological tissue including a tumor inside.
Results and Conclusion: The time-dependent study been applied by COMSOL has assured that the proposed deduced mathematical model may be considered as a simplified, easy, and fast startup base for scientific researchers to numerically model and simulate biomedical PA signals’ generation and propagation process utilizing any proper software like COMSOL.
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Gadallah MT, Mohamed AEA, Hefnawy A, Zidan H, El-banby G, Badawy SM. A Mathematical Model for Simulating Photoacoustic Signal Generation Process in Biological Tissues.. [DOI: 10.21203/rs.3.rs-2928563/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Background
Biomedical photoacoustic imaging (PAI) is a hybrid imaging modality based on the laser-generated ultrasound waves due to the photoacoustic (PA) effect physical phenomenon that has been reported firstly by A. G. Bell in 1880. Numerical modeling based simulation for PA signal generation process in biological tissues helps researchers for decreasing error trials in-vitro and hence decreasing error rates for in-vivo experiments. Numerical modeling methods help in obtaining a rapid modeling procedure comparable to pure mathematics. However, if a proper simplified mathematical model can be founded before applying numerical modeling techniques, it will be a great advantage for the overall numerical model. More scientific theories, equations, and assumptions through the biomedical PA imaging research literature have been proposed trying to mathematically model the complete PA signal generation and propagation process in biological tissues. However, most of them have so complicated details. Hence, the researchers, especially the beginners, will find a hard difficulty to explore and obtain a proper simplified mathematical model describing the process. That’s why this paper is introduced.
Methods
In this paper we have tried to simplify understanding for the biomedical PA wave’s generation and propagation process, deducing a simplified mathematical model for the whole process. The proposed deduced model is based on three steps: a- pulsed laser irradiance, b- diffusion of light through biological tissue, and c- acoustic pressure wave generation and propagation from the target tissue to the ultrasound transducer surface.
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17
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Jiang X, Shen M, Lun DPK, Chen W, Somekh MG. A total-internal-reflection-based Fabry-Pérot resonator for ultra-sensitive wideband ultrasound and photoacoustic applications. PHOTOACOUSTICS 2023; 30:100466. [PMID: 36926115 PMCID: PMC10011501 DOI: 10.1016/j.pacs.2023.100466] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/26/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
In photoacoustic and ultrasound imaging, optical transducers offer a unique potential to provide higher responsivity, wider bandwidths, and greatly reduced electrical and acoustic impedance mismatch when compared with piezoelectric transducers. In this paper, we propose a total-internal-reflection-based Fabry-Pérot resonator composed of a 12-nm-thick gold layer and a dielectric resonant cavity. The resonator uses the same Kretschmann configuration as surface plasmon resonators (SPR). The resonators were analyzed both theoretically and experimentally. The experimental results were compared with those for an SPR for benchmarking. The 1.9-μm-thick-PMMA- and 3.4-μm-thick-PDMS-based resonators demonstrated responsivities of 3.6- and 30-fold improvements compared with the SPR, respectively. The measured bandwidths for the PMMA, PDMS devices are 110 MHz and 75 MHz, respectively. Single-shot sensitivity of 160 Pa is obtained for the PDMS device. The results indicate that, with the proposed resonator in imaging applications, sensitivity and the signal-to-noise ratio can be improved significantly without compromising the bandwidth.
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Affiliation(s)
- Xiaoping Jiang
- Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, Guangdong, China
| | - Mengqi Shen
- Guangdong Laboratory of Machine Perception and Intelligent Computing, The Faculty of Engineering, Shenzhen MSU-BIT University, Shenzhen 518172, Guangdong, China
| | - Daniel Pak-Kong Lun
- Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Wen Chen
- Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Michael G. Somekh
- The Faculty of Engineering, University of Nottingham, Nottingham, UK
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18
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Ma J, Zhao J, Chen H, Sun LP, Li J, Guan BO. Transparent microfiber Fabry-Perot ultrasound sensor with needle-shaped focus for multiscale photoacoustic imaging. PHOTOACOUSTICS 2023; 30:100482. [PMID: 37025114 PMCID: PMC10070891 DOI: 10.1016/j.pacs.2023.100482] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/01/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
Photoacoustic tomography emerged as a promising tool for noninvasive biomedical imaging and diseases diagnosis. However, most of the current piezoelectric ultrasound transducers suffer optical opacity and tissue-mismatched acoustic impedance, hindering the miniaturization and integration of the system for multiscale and multimodal imaging. Here, a transparent polydimethylsiloxane (PDMS) encapsulated optical microfiber ultrasound sensor was demonstrated for photoacoustic imaging with scalable spatial resolution and penetration depth. The sensor comprised a microfiber loop sandwiched by a pair of in-line Bragg gratings, which formed an ultrasound-sensitive Fabry-Perot cavity allowing free delivery of ultrasound/light beams and unique needle-shaped ultrasound focusing along the penetration depth. The sensor with a detection limit of ∼ 700 Pa and a bandwidth of ∼ 10 MHz was applied for multiscale photoacoustic imaging of mouse ear and brain vasculatures. With advantages of flexibility, optical transparence and focusing capability, the sensor offers new opportunities for developing photoacoustic/ultrasound imaging devices for biomedical and clinic applications.
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19
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Saucourt J, Moreau A, Lumeau J, Rigneault H, Chaigne T. Fast interrogation wavelength tuning for all-optical photoacoustic imaging. OPTICS EXPRESS 2023; 31:11164-11172. [PMID: 37155758 DOI: 10.1364/oe.476747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Optical detection of ultrasound for photoacoustic imaging provides a large bandwidth and high sensitivity at high acoustic frequencies. Therefore, higher spatial resolutions can be achieved using Fabry-Pérot cavity sensors than conventional piezoelectric detection. However, fabrication constraints during the deposition of the sensing polymer layer require precise control of the interrogation beam wavelength to provide optimal sensitivity. This is commonly achieved by employing slowly tunable narrowband lasers as interrogation sources, hence limiting the acquisition speed. We propose instead to use a broadband source and a fast-tunable acousto-optic filter to adjust the interrogation wavelength at each pixel within a few microseconds. We demonstrate the validity of this approach by performing photoacoustic imaging with a highly inhomogeneous Fabry-Pérot sensor.
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20
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Tang Y, Tang S, Huang C, Klippel P, Ma C, Caso N, Chen S, Jing Y, Yao J. High-fidelity deep functional photoacoustic tomography enhanced by virtual point sources. PHOTOACOUSTICS 2023; 29:100450. [PMID: 36685991 PMCID: PMC9852650 DOI: 10.1016/j.pacs.2023.100450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/19/2022] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Photoacoustic tomography (PAT), a hybrid imaging modality that acoustically detects the optical absorption contrast, is a promising technology for imaging hemodynamic functions in deep tissues far beyond the traditional optical microscopy. However, the most clinically compatible PAT often suffers from the poor image fidelity, mostly due to the limited detection view of the linear ultrasound transducer array. PAT can be improved by employing highly-absorbing contrast agents such as droplets and nanoparticles, which, however, have low clinical translation potential due to safety concerns and regulatory hurdles imposed by these agents. In this work, we have developed a new methodology that can fundamentally improve PAT's image fidelity without hampering any of its functional capability or clinical translation potential. By using clinically-approved microbubbles as virtual point sources that strongly and isotropically scatter the local pressure waves generated by surrounding hemoglobin, we can overcome the limited-detection-view problem and achieve high-fidelity functional PAT in deep tissues, a technology referred to as virtual-point-source PAT (VPS-PAT). We have thoroughly investigated the working principle of VPS-PAT by numerical simulations and in vitro phantom experiments, clearly showing the signal origin of VPSs and the resultant superior image fidelity over traditional PAT. We have also demonstrated in vivo applications of VPT-PAT for functional small-animal studies with physiological challenges. We expect that VPS-PAT can find broad applications in biomedical research and accelerated translation to clinical impact.
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Affiliation(s)
- Yuqi Tang
- Photoacoustic Imaging Lab, Department of Biomedical Engineering, Duke University, Durham, NC, the United States of America
| | - Shanshan Tang
- Ultrasound Imaging Lab, Department of Biomedical Engineering, Mayo Clinic, Rochester, MN, the United States of America
| | - Chengwu Huang
- Ultrasound Imaging Lab, Department of Biomedical Engineering, Mayo Clinic, Rochester, MN, the United States of America
| | - Paul Klippel
- Graduate Program in Acoustic and Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, the United States of America
| | - Chenshuo Ma
- Photoacoustic Imaging Lab, Department of Biomedical Engineering, Duke University, Durham, NC, the United States of America
| | - Nathan Caso
- Graduate Program in Acoustic and Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, the United States of America
| | - Shigao Chen
- Ultrasound Imaging Lab, Department of Biomedical Engineering, Mayo Clinic, Rochester, MN, the United States of America
| | - Yun Jing
- Graduate Program in Acoustic and Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, the United States of America
| | - Junjie Yao
- Photoacoustic Imaging Lab, Department of Biomedical Engineering, Duke University, Durham, NC, the United States of America
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21
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Li B, Zhang R, Bi R, Olivo M. Applications of Optical Fiber in Label-Free Biosensors and Bioimaging: A Review. BIOSENSORS 2022; 13:64. [PMID: 36671899 PMCID: PMC9855469 DOI: 10.3390/bios13010064] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
Biosensing and bioimaging are essential in understanding biological and pathological processes in a living system, for example, in detecting and understanding certain diseases. Optical fiber has made remarkable contributions to the biosensing and bioimaging areas due to its unique advantages of compact size, immunity to electromagnetic interference, biocompatibility, fast response, etc. This review paper will present an overview of seven common types of optical fiber biosensors and optical fiber-based ultrasound detection in photoacoustic imaging (PAI) and the applications of these technologies in biosensing and bioimaging areas. Of course, there are many types of optical fiber biosensors. Still, this paper will review the most common ones: optical fiber grating, surface plasmon resonance, Sagnac interferometer, Mach-Zehnder interferometer, Michelson interferometer, Fabry-Perot Interferometer, lossy mode resonance, and surface-enhanced Raman scattering. Furthermore, different optical fiber techniques for detecting ultrasound in PAI are summarized. Finally, the main challenges and future development direction are briefly discussed.
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Affiliation(s)
| | | | - Renzhe Bi
- Translational Biophotonics Laboratory, Institute of Bioengineering and Bioimaging, Agency for Science, Technology and Research (A*STAR), Singapore 138667, Singapore
| | - Malini Olivo
- Translational Biophotonics Laboratory, Institute of Bioengineering and Bioimaging, Agency for Science, Technology and Research (A*STAR), Singapore 138667, Singapore
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22
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Menozzi L, Yang W, Feng W, Yao J. Sound out the impaired perfusion: Photoacoustic imaging in preclinical ischemic stroke. Front Neurosci 2022; 16:1055552. [PMID: 36532279 PMCID: PMC9751426 DOI: 10.3389/fnins.2022.1055552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 11/17/2022] [Indexed: 09/19/2023] Open
Abstract
Acoustically detecting the optical absorption contrast, photoacoustic imaging (PAI) is a highly versatile imaging modality that can provide anatomical, functional, molecular, and metabolic information of biological tissues. PAI is highly scalable and can probe the same biological process at various length scales ranging from single cells (microscopic) to the whole organ (macroscopic). Using hemoglobin as the endogenous contrast, PAI is capable of label-free imaging of blood vessels in the brain and mapping hemodynamic functions such as blood oxygenation and blood flow. These imaging merits make PAI a great tool for studying ischemic stroke, particularly for probing into hemodynamic changes and impaired cerebral blood perfusion as a consequence of stroke. In this narrative review, we aim to summarize the scientific progresses in the past decade by using PAI to monitor cerebral blood vessel impairment and restoration after ischemic stroke, mostly in the preclinical setting. We also outline and discuss the major technological barriers and challenges that need to be overcome so that PAI can play a more significant role in preclinical stroke research, and more importantly, accelerate its translation to be a useful clinical diagnosis and management tool for human strokes.
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Affiliation(s)
- Luca Menozzi
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Wei Yang
- Multidisciplinary Brain Protection Program, Department of Anesthesiology, Duke University, Durham, NC, United States
| | - Wuwei Feng
- Department of Neurology, Duke University School of Medicine, Durham, NC, United States
| | - Junjie Yao
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
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23
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Song W, Dong Y, Shan Y, Yang F, Min C, Yuan X. Ultrasensitive broadband photoacoustic microscopy based on common-path interferometric surface plasmon resonance sensing. PHOTOACOUSTICS 2022; 28:100419. [PMID: 36339639 PMCID: PMC9634362 DOI: 10.1016/j.pacs.2022.100419] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 09/15/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Ultrafast and sensitive response of surface plasmon polaritons to the ultrasonically-modulated changes in refractive index of the water allows photoacoustic impulses to be measured using surface plasmon resonance (SPR) sensors. However, the sensing modalities always suffer from either low sensitivity or instable signal output, possibly precluding imaging recovery. By exploiting that pressure transients can substantially produce phase shift in p-polarized optical reflection but have no impact on s-polarized component in SPR sensing, we develop a common-path interferometric SPR sensor for photoacoustic measurement, in which time-varying light interference between photoacoustically-perturbed p-polarized beam and its orthogonal s-polarized component of a single interrogation laser is monitored. Such configuration retains optimum photoacoustic measurement with concurrent very stable signal output, high sensitivity (noise-equivalent-pressure sensitivity of ∼95.6 Pa), and broad bandwidth (∼173 MHz). Volumetric microvascular imaging from mouse ear in vivo is obtained, suggesting that the novel sensing approach potentially advances biomedical photoacoustic applications.
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Cai J, Wang Y, Jiang D, Zhang S, Gu YA, Lou L, Gao F, Wu T. Beyond fundamental resonance mode: high-order multi-band ALN PMUT for in vivo photoacoustic imaging. MICROSYSTEMS & NANOENGINEERING 2022; 8:116. [PMID: 36389053 PMCID: PMC9643525 DOI: 10.1038/s41378-022-00426-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 06/16/2023]
Abstract
This paper reports on an aluminum nitride (AlN) piezoelectric micromachined ultrasound transducer (PMUT) array for photoacoustic (PA) imaging, where the high-order resonance modes of the PMUT are utilized to improve imaging resolution. A flexural vibration mode (FVM) PMUT is fabricated and applied in a photoacoustic imaging (PAI) system. Specifically, the microelectromechanical system (MEMS)-based PMUT is suitable for PA endoscopic imaging of blood vessels and bronchi due to its miniature size and high sensitivity. More importantly, AlN is a nontoxic material, which makes it harmless for biomedical applications. In the PAI system, the AlN PMUT array is used to detect PA signals, and the acousto-mechanical response is designed and optimized at the PMUT's fundamental resonance. In this work, we focus on the high-order resonance performance of the PMUT PAI beyond the fundamental resonance. The acoustic and electrical responses of the PMUT's high-order resonance modes are characterized and analyzed. The fundamental and three high-order resonance bandwidths are 2.2, 8.8, 18.5, and 48.2 kHz. Compared with the resolution at the fundamental resonance mode, the resolutions at third- and fourth-order resonance modes increase by 38.7% and 76.9% in a phantom experiment. The high-order resonance modes of the AlN PMUT sensor array provide higher central frequency and wider bandwidth for PA signal detection, which increase the resolution of PAI compared to the PMUT working at the fundamental resonance mode.
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Affiliation(s)
- Junxiang Cai
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Institute of Microsystem and Information Technology, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yiyun Wang
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Institute of Microsystem and Information Technology, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Daohuai Jiang
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
| | - Songsong Zhang
- School of Microelectronics, Shanghai University, Shanghai, China
- Shanghai Industrial μTechnology Research Institute, Shanghai, China
| | - Yuandong Alex Gu
- School of Microelectronics, Shanghai University, Shanghai, China
- Shanghai Industrial μTechnology Research Institute, Shanghai, China
| | - Liang Lou
- School of Microelectronics, Shanghai University, Shanghai, China
- Shanghai Industrial μTechnology Research Institute, Shanghai, China
| | - Fei Gao
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Institute of Microsystem and Information Technology, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
- Shanghai Engineering Research Center of Energy Efficient and Custom AI IC, Shanghai, China
| | - Tao Wu
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China
- Shanghai Institute of Microsystem and Information Technology, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
- Shanghai Engineering Research Center of Energy Efficient and Custom AI IC, Shanghai, China
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25
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Wen Y, Guo D, Zhang J, Liu X, Liu T, Li L, Jiang S, Wu D, Jiang H. Clinical photoacoustic/ultrasound dual-modal imaging: Current status and future trends. Front Physiol 2022; 13:1036621. [PMID: 36388111 PMCID: PMC9651137 DOI: 10.3389/fphys.2022.1036621] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 10/05/2022] [Indexed: 08/24/2023] Open
Abstract
Photoacoustic tomography (PAT) is an emerging biomedical imaging modality that combines optical and ultrasonic imaging, providing overlapping fields of view. This hybrid approach allows for a natural integration of PAT and ultrasound (US) imaging in a single platform. Due to the similarities in signal acquisition and processing, the combination of PAT and US imaging creates a new hybrid imaging for novel clinical applications. Over the recent years, particular attention is paid to the development of PAT/US dual-modal systems highlighting mutual benefits in clinical cases, with an aim of substantially improving the specificity and sensitivity for diagnosis of diseases. The demonstrated feasibility and accuracy in these efforts open an avenue of translating PAT/US imaging to practical clinical applications. In this review, the current PAT/US dual-modal imaging systems are discussed in detail, and their promising clinical applications are presented and compared systematically. Finally, this review describes the potential impacts of these combined systems in the coming future.
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Affiliation(s)
- Yanting Wen
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
- School of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, China
| | - Dan Guo
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
| | - Jing Zhang
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
- School of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, China
| | - Xiaotian Liu
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
| | - Ting Liu
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
| | - Lu Li
- Department of Ultrasound Imaging, The Fifth People’s Hospital of Chengdu, Chengdu, China
| | - Shixie Jiang
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States
| | - Dan Wu
- School of Computer Science and Technology, Chongqing University of Posts and Telecommunications, Chongqing, China
| | - Huabei Jiang
- Department of Medical Engineering, University of South Florida, Tampa, FL, United States
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Mirg S, Turner KL, Chen H, Drew PJ, Kothapalli SR. Photoacoustic imaging for microcirculation. Microcirculation 2022; 29:e12776. [PMID: 35793421 PMCID: PMC9870710 DOI: 10.1111/micc.12776] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/13/2022] [Accepted: 06/28/2022] [Indexed: 01/26/2023]
Abstract
Microcirculation facilitates the blood-tissue exchange of nutrients and regulates blood perfusion. It is, therefore, essential in maintaining tissue health. Aberrations in microcirculation are potentially indicative of underlying cardiovascular and metabolic pathologies. Thus, quantitative information about it is of great clinical relevance. Photoacoustic imaging (PAI) is a capable technique that relies on the generation of imaging contrast via the absorption of light and can image at micron-scale resolution. PAI is especially desirable to map microvasculature as hemoglobin strongly absorbs light and can generate a photoacoustic signal. This paper reviews the current state of the art for imaging microvascular networks using photoacoustic imaging. We further describe how quantitative information about blood dynamics such as the total hemoglobin concentration, oxygen saturation, and blood flow rate is obtained using PAI. We also discuss its importance in understanding key pathophysiological processes in neurovascular, cardiovascular, ophthalmic, and cancer research fields. We then discuss the current challenges and limitations of PAI and the approaches that can help overcome these limitations. Finally, we provide the reader with an overview of future trends in the field of PAI for imaging microcirculation.
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Affiliation(s)
- Shubham Mirg
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Kevin L. Turner
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Haoyang Chen
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Patrick J. Drew
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, USA
- Department of Neurosurgery, Pennsylvania State University, University Park, PA 16802, USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Sri-Rajasekhar Kothapalli
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
- Penn State Cancer Institute, Pennsylvania State University, Hershey, PA 17033, USA
- Graduate Program in Acoustics, Pennsylvania State University, University Park, PA 16802, USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA
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Yoon C, Kang J, Song TK, Chang JH. Elevational Synthetic Aperture Focusing for Three-Dimensional Photoacoustic Imaging Using a Clinical One-Dimensional Array Transducer. IEEE Trans Biomed Eng 2022; 69:2817-2825. [PMID: 35226597 PMCID: PMC9520468 DOI: 10.1109/tbme.2022.3154754] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Two-dimensional (2D) photoacoustic (PA) imaging based on array transducers provide high spatial resolution in the lateral direction by adopting receive dynamic focusing. However, the quality of PA image is often deteriorated by poor elevational resolution which is achieved by an acoustic lens. To overcome this limitation, we present a three-dimensional (3D) image reconstruction method using a commercial one-dimensional (1D) array transducer. METHODS In the method, the elevational resolution is improved by applying synthetic aperture focusing (SAF) technique along the elevational direction. For this, a commercially available 1D array transducer with an acoustic lens is modeled and appropriate synthetic focusing delay that can minimize the effect of the acoustic lens is derived by mathematical analysis. RESULTS From the simulation and experiment results, it was demonstrated that the proposed method can enhance the image quality of PA imaging, i.e., elevational resolution and signal-to-noise ratio (SNR). CONCLUSION 3D PA images with improved elevational resolution were achieved using a clinical 1D array transducer. SIGNIFICANCE The presented method may be useful for clinical application such as detecting microcalcification, imaging of tumor vasculature and guidance of biopsy in real time.
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Hornig GJ, Scheuer KG, Dew EB, Zemp R, DeCorby RG. Ultrasound sensing at thermomechanical limits with optomechanical buckled-dome microcavities. OPTICS EXPRESS 2022; 30:33083-33096. [PMID: 36242356 DOI: 10.1364/oe.463588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 08/11/2022] [Indexed: 06/16/2023]
Abstract
We describe the use of monolithic, buckled-dome cavities as ultrasound sensors. Patterned delamination within a compressively stressed thin film stack produces high-finesse plano-concave optical resonators with sealed and empty cavity regions. The buckled mirror also functions as a flexible membrane, highly responsive to changes in external pressure. Owing to their efficient opto-acousto-mechanical coupling, thermal-displacement-noise limited sensitivity is achieved at low optical interrogation powers and for modest optical (Q ∼ 103) and mechanical (Q ∼ 102) quality factors. We predict and verify broadband (up to ∼ 5 MHz), air-coupled ultrasound detection with noise-equivalent pressure (NEP) as low as ∼ 30-100 µPa/Hz1/2. This corresponds to an ultrasonic force sensitivity ∼ 2 × 10-13 N/Hz1/2 and enables the detection of MHz-range signals propagated over distances as large as ∼ 20 cm in air. In water, thermal-noise-limited sensitivity is demonstrated over a wide frequency range (up to ∼ 30 MHz), with NEP as low as ∼ 100-800 µPa/Hz1/2. These cavities exhibit a nearly omnidirectional response, while being ∼ 3-4 orders of magnitude more sensitive than piezoelectric devices of similar size. Easily realized as large arrays and naturally suited to direct coupling by free-space beams or optical fibers, they offer significant practical advantages over competing optical devices, and thus could be of interest for several emerging applications in medical and industrial ultrasound imaging.
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29
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Chen H, Agrawal S, Osman M, Minotto J, Mirg S, Liu J, Dangi A, Tran Q, Jackson T, Kothapalli SR. A Transparent Ultrasound Array for Real-Time Optical, Ultrasound, and Photoacoustic Imaging. BME FRONTIERS 2022; 2022:9871098. [PMID: 37850172 PMCID: PMC10521654 DOI: 10.34133/2022/9871098] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 04/28/2022] [Indexed: 10/19/2023] Open
Abstract
Objective and Impact Statement. Simultaneous imaging of ultrasound and optical contrasts can help map structural, functional, and molecular biomarkers inside living subjects with high spatial resolution. There is a need to develop a platform to facilitate this multimodal imaging capability to improve diagnostic sensitivity and specificity. Introduction. Currently, combining ultrasound, photoacoustic, and optical imaging modalities is challenging because conventional ultrasound transducer arrays are optically opaque. As a result, complex geometries are used to coalign both optical and ultrasound waves in the same field of view. Methods. One elegant solution is to make the ultrasound transducer transparent to light. Here, we demonstrate a novel transparent ultrasound transducer (TUT) linear array fabricated using a transparent lithium niobate piezoelectric material for real-time multimodal imaging. Results. The TUT-array consists of 64 elements and centered at ~6 MHz frequency. We demonstrate a quad-mode ultrasound, Doppler ultrasound, photoacoustic, and fluorescence imaging in real-time using the TUT-array directly coupled to the tissue mimicking phantoms. Conclusion. The TUT-array successfully showed a multimodal imaging capability and has potential applications in diagnosing cancer, neurological, and vascular diseases, including image-guided endoscopy and wearable imaging.
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Affiliation(s)
- Haoyang Chen
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sumit Agrawal
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Mohamed Osman
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Josiah Minotto
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Shubham Mirg
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jinyun Liu
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Ajay Dangi
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Quyen Tran
- School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Thomas Jackson
- School of Electrical Engineering and Computer Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sri-Rajasekhar Kothapalli
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
- Penn State Cancer Institute, The Pennsylvania State University, Hershey, PA 17033, USA
- Graduate Program in Acoustics, The Pennsylvania State University, University Park, PA 16802, USA
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Ichihashi H, Ueno S, Fukunaga T, Takayanagi S, Matsukawa M. Signal Amplification of the Transient Response Measured by the Subnanosecond Pump-Probe Method Based on Surface Plasmon Resonance. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:2152-2161. [PMID: 35389864 DOI: 10.1109/tuffc.2022.3165519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A pump-probe system with a subnanosecond pulsed laser is expected to be a compact and inexpensive transient spectroscopic system that enables nondestructive and noncontact evaluations of the physical properties. However, an improvement in the sensitivity and a theoretical model to complement the measurement signal are necessary to obtain the transient signal precisely because of the low sensitivity and large time resolution. We have developed a highly sensitive pump-probe system with a subnanosecond pulsed laser that combines signal amplification based on surface plasmon resonance (SPR) in this study. An integrated theoretical model of the transient response obtained by a subnanosecond pump-probe under the SPR condition was proposed. Our model consisted of the profile descriptions of the used pulse source, temperature change, generated thermoelastic stress, estimated permittivity change in the metal film, and estimated reflectivity change. The theoretical estimations in the time domain and the incident angle dependence were compared with those of the experimental results to verify our theory. As a result, the estimations were well in agreement with the experimental results. Moreover, the signal-amplification mechanism based on SPR was discussed using our theory. The amplification was caused by the broadening of the resonant curve of SPR and the shift of the resonant angle, which seemed to come from the increase in the electron-phonon scattering rate and the thermal expansion of the metal film, respectively. A clear mechanism of SPR-based signal amplification of the subnanosecond pump-probe was identified through experimental and theoretical approaches.
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31
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Song W, Wang YC, Chen H, Li X, Zhou L, Min C, Zhu S, Yuan X. Label-free identification of human glioma xenograft of mouse brain with quantitative ultraviolet photoacoustic histology imaging. JOURNAL OF BIOPHOTONICS 2022; 15:e202100329. [PMID: 35000293 DOI: 10.1002/jbio.202100329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 12/14/2021] [Accepted: 01/07/2022] [Indexed: 06/14/2023]
Abstract
The ability to unveil molecular specificities of endogenous nonfluorescent chromophores of ultraviolet photoacoustic imaging technology enables label-free histology imaging of tissue specimens. In this work, we exploit ultraviolet photoacoustic microscopy for identifying human glioma xenograft of mouse brain ex vivo. Intrinsically excellent imaging contrast of cell nucleus at ultraviolet photoacoustic illumination along with good spatial resolution allows for discerning the brain glioma of freshly-harvested thick brain slices, which circumvents laborious time-consuming preparations of the tissue specimens including micrometer-thick slicing and H&E staining that are prerequisites in standard histology analysis. The identification of tumor margins and quantitative analysis of tumor areas is implemented, representing good agreement with the standard H&E-stained observations. Quantitative ultraviolet photoacoustic microscopy can access fast pathological assessment to the brain tissues, and thus potentially facilitates intraoperative brain tumor resection to precisely remove all cancerous cells and preserve healthy tissue for maintaining its essential function.
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Affiliation(s)
- Wei Song
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Ya-Chao Wang
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, China
- The Institute Translational Medicine, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, China
| | - Huang Chen
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Xiangzhu Li
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen, China
| | - Lingxiao Zhou
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Changjun Min
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Siwei Zhu
- The Institute of Translational Medicine, Tianjin Union Medical Center of Nankai University, Tianjin, China
| | - Xiaocong Yuan
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
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32
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Volodarsky O, Hazan Y, Nagli M, Rosenthal A. Burst-mode pulse interferometry for enabling low-noise multi-channel optical detection of ultrasound. OPTICS EXPRESS 2022; 30:8959-8973. [PMID: 35299336 DOI: 10.1364/oe.449630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Ultrasound detection via optical resonators can achieve high levels of miniaturization and sensitivity as compared to piezoelectric detectors, but its scale-up from a single detector to an array is highly challenging. While the use of wideband sources may enable parallel interrogation of multiple resonators, it comes at the cost of reduction in the optical power, and ultimately in sensitivity, per channel. In this work we have developed a new interferometric approach to overcome this signal loss by using high-power bursts that are synchronized with the time window in which ultrasound detection is performed. Each burst is composed of a train of low-noise optical pulses which are sufficiently wideband to interrogate an array of resonators with non-overlapping spectra. We demonstrate our method, termed burst-mode pulse interferometry, for interrogating a single resonator in which the optical power was reduced to emulate the power loss per channel that occurs in parallel interrogation of 20 to 200 resonators. The use of bursts has led to up 25-fold improvement in sensitivity without affecting the shape of the acoustic signals, potentially enabling parallel low-noise interrogation of resonator arrays with a single source.
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33
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Dong B, Yao J, Deán-Ben XL. Editorial: Advances in Photoacoustic Neuroimaging. Front Neurosci 2022; 16:859515. [PMID: 35321095 PMCID: PMC8934976 DOI: 10.3389/fnins.2022.859515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Biqin Dong
- Academy for Engineering and Technology, Fudan University, Shanghai, China
- *Correspondence: Biqin Dong
| | - Junjie Yao
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
| | - Xosé Luís Deán-Ben
- Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich, Switzerland
- Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland
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34
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Fu B, Cheng Y, Shang C, Li J, Wang G, Zhang C, Sun J, Ma J, Ji X, He B. Optical ultrasound sensors for photoacoustic imaging: a narrative review. Quant Imaging Med Surg 2022; 12:1608-1631. [PMID: 35111652 DOI: 10.21037/qims-21-605] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/23/2021] [Indexed: 11/06/2022]
Abstract
Optical ultrasound sensors have been increasingly employed in biomedical diagnosis and photoacoustic imaging (PAI) due to high sensitivity and resolution. PAI could visualize the distribution of ultrasound excited by laser pulses in biological tissues. The information of tissues is detected by ultrasound sensors in order to reconstruct structural images. However, traditional ultrasound transducers are made of piezoelectric films that lose sensitivity quadratically with the size reduction. In addition, the influence of electromagnetic interference limits further applications of traditional ultrasound transducers. Therefore, optical ultrasound sensors are developed to overcome these shortcomings. In this review, optical ultrasound sensors are classified into resonant and non-resonant ones in view of physical principles. The principles and basic parameters of sensors are introduced in detail. Moreover, the state of the art of optical ultrasound sensors and applications in PAI are also presented. Furthermore, the merits and drawbacks of sensors based on resonance and non-resonance are discussed in perspectives. We believe this review could provide researchers with a better understanding of the current status of optical ultrasound sensors and biomedical applications.
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Affiliation(s)
- Bo Fu
- BUAA-CCMU Advanced Innovation Center for Big Data-Based Precision Medicine, School of Engineering Medicine, Beihang University, Beijing, China.,School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China.,Key Laboratory of Big Data-Based Precision Medicine, Ministry of Industry and Information Technology, Interdisciplinary Innovation Institute of Medicine and Engineering, Beihang University, Beijing, China
| | - Yuan Cheng
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
| | - Ce Shang
- BUAA-CCMU Advanced Innovation Center for Big Data-Based Precision Medicine, School of Engineering Medicine, Beihang University, Beijing, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Jing Li
- BUAA-CCMU Advanced Innovation Center for Big Data-Based Precision Medicine, School of Engineering Medicine, Beihang University, Beijing, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Gang Wang
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
| | - Chenghong Zhang
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
| | - Jingxuan Sun
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
| | - Jianguo Ma
- BUAA-CCMU Advanced Innovation Center for Big Data-Based Precision Medicine, School of Engineering Medicine, Beihang University, Beijing, China.,School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China.,Key Laboratory of Big Data-Based Precision Medicine, Ministry of Industry and Information Technology, Interdisciplinary Innovation Institute of Medicine and Engineering, Beihang University, Beijing, China
| | - Xunming Ji
- Neurosurgery Department of Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Boqu He
- BUAA-CCMU Advanced Innovation Center for Big Data-Based Precision Medicine, School of Engineering Medicine, Beihang University, Beijing, China.,School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
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35
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Rong Q, Lee Y, Tang Y, Vu T, Taboada C, Zheng W, Xia J, Czaplewski DA, Zhang HF, Sun C, Yao J. High-Frequency 3D Photoacoustic Computed Tomography Using an Optical Microring Resonator. BME FRONTIERS 2022; 2022:9891510. [PMID: 36818003 PMCID: PMC9933894 DOI: 10.34133/2022/9891510] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
3D photoacoustic computed tomography (3D-PACT) has made great advances in volumetric imaging of biological tissues, with high spatial-temporal resolutions and large penetration depth. The development of 3D-PACT requires high-performance acoustic sensors with a small size, large detection bandwidth, and high sensitivity. In this work, we present a new high-frequency 3D-PACT system that uses a micro-ring resonator (MRR) as the acoustic sensor. The MRR sensor has a size of 80 μm in diameter, and was fabricated using the nanoimprint lithography technology. Using the MRR sensor, we have developed a transmission-mode 3D-PACT system that has achieved a detection bandwidth of ~23 MHz, an imaging depth of ~8 mm, a lateral resolution of 114 μm, and an axial resolution of 57 μm. We have demonstrated the 3D PACT's performance on in vitro phantoms, ex vivo mouse brain, and in vivo mouse ear and tadpole. The MRR-based 3D-PACT system can be a promising tool for structural, functional, and molecular imaging of biological tissues at depths.
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Affiliation(s)
- Qiangzhou Rong
- Department of Biomedical Engineering, Duke University, Durham, NC, USA 27708
| | - Youngseop Lee
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.,Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Yuqi Tang
- Department of Biomedical Engineering, Duke University, Durham, NC, USA 27708
| | - Tri Vu
- Department of Biomedical Engineering, Duke University, Durham, NC, USA 27708
| | - Carlos Taboada
- Department of Biomedical Engineering, Duke University, Durham, NC, USA 27708
| | - Wenhan Zheng
- Optical & Ultrasonic Imaging Laboratory, University at Buffalo, North Campus Buffalo, NY 14260, USA
| | - Jun Xia
- Optical & Ultrasonic Imaging Laboratory, University at Buffalo, North Campus Buffalo, NY 14260, USA
| | - David A. Czaplewski
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Cheng Sun
- Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Junjie Yao
- Department of Biomedical Engineering, Duke University, Durham, NC, USA 27708
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Baumann E, Pohle U, Zhang E, Allen T, Villringer C, Pulwer S, Gerhardt H, Laufer J. A backward-mode optical-resolution photoacoustic microscope for 3D imaging using a planar Fabry-Pérot sensor. PHOTOACOUSTICS 2021; 24:100293. [PMID: 34466380 PMCID: PMC8385441 DOI: 10.1016/j.pacs.2021.100293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/23/2021] [Accepted: 08/08/2021] [Indexed: 06/13/2023]
Abstract
Optical-resolution photoacoustic microscopy (OR-PAM) combines high spatial resolution and strong absorption-based contrast in tissue, which has enabled structural and spectroscopic imaging of endogenous chromophores, primarily hemoglobin. Conventional piezoelectric ultrasound transducers are typically placed far away from the photoacoustic source due to their opacity, which reduces acoustic sensitivity. Optical ultrasound sensors are an alternative as their transparency allows them to be positioned close to the sample with minimal source-detector distances. In this work, a backward-mode OR-PAM system based on a planar Fabry-Pérot ultrasound sensor and coaxially aligned excitation and interrogation beams was developed. Two 3D imaging modes, using raster-scanning for enhanced image quality and continuous-scanning for fast imaging, were implemented and tested on a leaf skeleton phantom. In fast imaging mode, a scan-rate of 100,000 A-lines/s was achieved. 3D images of a zebrafish embryo were acquired in vivo in raster-scanning mode. The transparency of the FP sensor in the visible and near-infrared wavelength region makes it suitable for combined functional and molecular imaging applications using OR-PAM and multi-photon fluorescence microscopy.
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Affiliation(s)
- Elisabeth Baumann
- Integrative Vascular Biology Laboratory, Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125, Berlin, Germany
- Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Ulrike Pohle
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-danckelmann-platz 3, 06120, Halle (Saale), Germany
| | - Edward Zhang
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, WC1E 6BT, UK
| | - Thomas Allen
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, WC1E 6BT, UK
| | - Claus Villringer
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-danckelmann-platz 3, 06120, Halle (Saale), Germany
- University of Applied Sciences Wildau, Hochschulring 1, 15745, Wildau, Germany
| | - Silvio Pulwer
- University of Applied Sciences Wildau, Hochschulring 1, 15745, Wildau, Germany
| | - Holger Gerhardt
- Integrative Vascular Biology Laboratory, Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125, Berlin, Germany
- Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Center for Cardiovascular Research), Partner site, Potsdamer Str. 58, 10785, Berlin, Germany
- Berlin Institute of Health (BIH), Anna-Louisa-Karsch-Straβe 2, 10178, Berlin, Germany
| | - Jan Laufer
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-danckelmann-platz 3, 06120, Halle (Saale), Germany
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Chen H, Mirg S, Osman M, Agrawal S, Cai J, Biskowitz R, Minotto J, Kothapalli SR. A High Sensitivity Transparent Ultrasound Transducer based on PMN-PT for Ultrasound and Photoacoustic Imaging. IEEE SENSORS LETTERS 2021; 5:2500804. [PMID: 35707748 PMCID: PMC9191846 DOI: 10.1109/lsens.2021.3122097] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We recently introduced piezoelectric lithium niobate (LN) based transparent ultrasound transducers (TUT) as a new platform for developing multimodal optical, ultrasound and photoacoustic imaging systems. However, LN based TUT is limited in its signal-to-noise ratio due to material's low piezoelectricity (d 33). In this paper, we report, for the first time, a 0.2 mm thick transparent lead magnesium niobate-lead titanate (PMN-PT) based TUT (PMN-PT-TUT) for ultrasound and photoacoustic applications and compared its performance with a 0.25 mm thick transparent LN based TUT (LN-TUT). To improve the ultrasound energy transmission efficiency, TUTs were fabricated with a two-matching-layer design. This resulted in a dual frequency response with center frequencies of 7.8 MHz/13.2 MHz and corresponding bandwidths of 28.2%/66.67% for PMN-PT-TUT, and center frequencies of 7.2 MHz/11.8 MHz and bandwidths of 36.1%/62.7% for LN-TUT. The optical transmission rate of PMN-PT-TUTs and LN-TUTs are measured as ~73% and ~91% respectively at 532 nm optical wavelength. The PMN-PT-TUT exhibited higher sensitivity compared to LN-TUT with a nearly three-fold higher pulse echo amplitude and more than two-fold higher photoacoustic amplitude. Furthermore, optical resolution photoacoustic microscopy (ORPAM) experiments on phantom targets demonstrated lateral resolutions of 7 μm and 5.1 μm, and axial resolutions of 285.6 μm and 375.9 μm for PMN-PT-TUT and LN-TUT respectively. These results indicated that PMN-PT is a viable alternative to LN for developing TUT based multimodal ultrasound and photoacoustic imaging systems.
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Affiliation(s)
- Haoyang Chen
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Shubham Mirg
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Mohamed Osman
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Sumit Agrawal
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Jiacheng Cai
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Ryan Biskowitz
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Josiah Minotto
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
| | - Sri-Rajasekhar Kothapalli
- Department of Biomedical Engineering, The Pennsylvania State University, State College, PA, 16802, USA
- Penn State Cancer Institute, The Pennsylvania State University, Hershey, PA, 17033, USA
- Graduate Program in Acoustics, The Pennsylvania State University, State College, PA 16802, USA
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Tserevelakis GJ, Chaban A, Klironomou E, Melessanaki K, Striova J, Zacharakis G. Revealing Hidden Features in Multilayered Artworks by Means of an Epi-Illumination Photoacoustic Imaging System. J Imaging 2021; 7:jimaging7090183. [PMID: 34564109 PMCID: PMC8472515 DOI: 10.3390/jimaging7090183] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/30/2021] [Accepted: 09/08/2021] [Indexed: 11/24/2022] Open
Abstract
Photoacoustic imaging is a novel, rapidly expanding technique, which has recently found several applications in artwork diagnostics, including the uncovering of hidden layers in paintings and multilayered documents, as well as the thickness measurement of optically turbid paint layers with high accuracy. However, thus far, all the presented photoacoustic-based imaging technologies dedicated to such measurements have been strictly limited to thin objects due to the detection of signals in transmission geometry. Unavoidably, this issue restricts seriously the applicability of the imaging method, hindering investigations over a wide range of cultural heritage objects with diverse geometrical and structural features. Here, we present an epi-illumination photoacoustic apparatus for diagnosis in heritage science, which integrates laser excitation and respective signal detection on one side, aiming to provide universal information in objects of arbitrary thickness and shape. To evaluate the capabilities of the developed system, we imaged thickly painted mock-ups, in an attempt to reveal hidden graphite layers covered by various optically turbid paints, and compared the measurements with standard near-infrared (NIR) imaging. The obtained results prove that photoacoustic signals reveal underlying sketches with up to 8 times improved contrast, thus paving the way for more relevant applications in the field.
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Affiliation(s)
- George J. Tserevelakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, GR-70013 Heraklion, Crete, Greece; (E.K.); (K.M.); (G.Z.)
- Correspondence: (G.J.T.); (A.C.)
| | - Antonina Chaban
- National Institute of Optics INO-CNR, 50125 Florence, Italy;
- Correspondence: (G.J.T.); (A.C.)
| | - Evgenia Klironomou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, GR-70013 Heraklion, Crete, Greece; (E.K.); (K.M.); (G.Z.)
| | - Kristalia Melessanaki
- Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, GR-70013 Heraklion, Crete, Greece; (E.K.); (K.M.); (G.Z.)
| | - Jana Striova
- National Institute of Optics INO-CNR, 50125 Florence, Italy;
| | - Giannis Zacharakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, GR-70013 Heraklion, Crete, Greece; (E.K.); (K.M.); (G.Z.)
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Alles EJ, Mackle EC, Noimark S, Zhang EZ, Beard PC, Desjardins AE. Freehand and video-rate all-optical ultrasound imaging. ULTRASONICS 2021; 116:106514. [PMID: 34280811 PMCID: PMC7611777 DOI: 10.1016/j.ultras.2021.106514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/30/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
All-optical ultrasound (AOUS) imaging, which uses light to both generate and detect ultrasound, is an emerging alternative to conventional electronic ultrasound imaging. To date, AOUS imaging has been performed using paradigms that either resulted in long acquisition times or employed bench-top imaging systems that were impractical for clinical use. In this work, we present a novel AOUS imaging paradigm where scanning optics are used to rapidly synthesise an imaging aperture. This paradigm enabled the first AOUS system with a flexible, handheld imaging probe, which represents a critical step towards clinical translation. This probe, which provides video-rate imaging and a real-time display, is demonstrated with phantoms and in vivo human tissue.
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Affiliation(s)
- Erwin J Alles
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom.
| | - Eleanor C Mackle
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - Sacha Noimark
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - Edward Z Zhang
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - Paul C Beard
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - Adrien E Desjardins
- Department of Medical Physics & Biomedical Engineering, University College London, Malet Place Engineering Building, London WC1E 6BT, United Kingdom; Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
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40
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Abstract
Photoacoustic imaging is a new type of noninvasive, nonradiation imaging modality that combines the deep penetration of ultrasonic imaging and high specificity of optical imaging. Photoacoustic imaging systems employing conventional ultrasonic sensors impose certain constraints such as obstructions in the optical path, bulky sensor size, complex system configurations, difficult optical and acoustic alignment, and degradation of signal-to-noise ratio. To overcome these drawbacks, an ultrasonic sensor in the optically transparent form has been introduced, as it enables direct delivery of excitation light through the sensors. In recent years, various types of optically transparent ultrasonic sensors have been developed for photoacoustic imaging applications, including optics-based ultrasonic sensors, piezoelectric-based ultrasonic sensors, and microelectromechanical system-based capacitive micromachined ultrasonic transducers. In this paper, the authors review representative transparent sensors for photoacoustic imaging applications. In addition, the potential challenges and future directions of the development of transparent sensors are discussed.
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41
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Zhu EY, Charles-Herrera M, Rewcastle C, Gad R, Qian L, Levi O. Real-time ultrasound sensing with a mode-optimized photonic crystal slab. OPTICS LETTERS 2021; 46:3372-3375. [PMID: 34264216 DOI: 10.1364/ol.430431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
Integrated photonic sensors can provide large scale, flexible detection schemes. Photonic crystal slabs (PCSs) offer a miniaturized platform for wideband, sensitive ultrasound detection by exploiting the photoelastic effect in water. However, poor modal overlap with the sensing medium and non-negligible absorption loss of the aqueous medium have previously limited PCS sensor performance. In this study, we detail the development and optimization of a PCS-based acoustic sensor by adding to it a low-loss high-index polymer cladding layer. Exploiting a mode-optimized TM-like optical resonance present in a PCS, with high bulk index sensitivity (>600nm/RIU) and quality factor Q (>8000), we demonstrate real-time ultrasound sensing at a noise equivalent pressure of 170 Pa (1.9Pa/Hz). The PCS sensor is backside-coupled to an optical fiber, which, along with its intensity-based ultrasound-sensing architecture, will allow us to scale up easily to a 2D array. This work paves the way to a sensitive compact ultrasound detector for photoacoustic-based diagnostics and monitoring of tissue.
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Abstract
In this review, the roles of detectors in various medical imaging techniques were described. Ultrasound, optical (near-infrared spectroscopy and optical coherence tomography) and thermal imaging, magnetic resonance imaging, computed tomography, single-photon emission tomography, positron emission tomography were the imaging modalities considered. For each methodology, the state of the art of detectors mainly used in the systems was described, emphasizing new technologies applied.
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43
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Ülgen O, Shnaiderman R, Zakian C, Ntziachristos V. Interferometric optical fiber sensor for optoacoustic endomicroscopy. JOURNAL OF BIOPHOTONICS 2021; 14:e202000501. [PMID: 33773073 DOI: 10.1002/jbio.202000501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/04/2021] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Optical fiber sensors can offer robust and miniaturized detection of wideband ultrasound, yielding high sensitivity and immunity to electromagnetic interference. However, the lack of cost-effective manufacturing methods prevents the disseminated use of these sensors in biomedical applications. In this study, we developed and optimized a simple method to create optical cavities with high-quality mirrors for acoustic sensing based on micro-manipulation of UV-curable optical adhesives and electroless chemical silver deposition. This approach enables the manufacturing of ultrasound sensors based on Fabry-Pérot interferometers on optical fiber tips with minimal production costs. Characterization and high-resolution optoacoustic imaging experiments show that the manufacturing process yielded a fiber sensor with a small NEP ( 11mPa/Hz ) over a broad detection bandwidth (25 MHz), generally outperforming conventional piezoelectric based transducers. We discuss how the new manufacturing process leads to a high-performance acoustic detector that, due to low cost, can be used as a disposable sensor.
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Affiliation(s)
- Okan Ülgen
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Rami Shnaiderman
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Christian Zakian
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
| | - Vasilis Ntziachristos
- Chair of Biological Imaging at the Central Institute for Translational Cancer Research (TranslaTUM), School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
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Goldfain AM, Yung CS, Briggman KA, Hwang J. Optical phase contrast imaging for absolute, quantitative measurements of ultrasonic fields with frequencies up to 20 MHz. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:4620. [PMID: 34241467 PMCID: PMC9889099 DOI: 10.1121/10.0005431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 06/03/2021] [Indexed: 06/13/2023]
Abstract
The technique of phase contrast imaging, combined with tomographic reconstructions, can rapidly measure ultrasonic fields propagating in water, including ultrasonic fields with complex wavefront shapes, which are difficult to characterize with standard hydrophone measurements. Furthermore, the technique can measure the absolute pressure amplitudes of ultrasonic fields without requiring a pressure calibration. Absolute pressure measurements have been previously demonstrated using optical imaging methods for ultrasonic frequencies below 2.5 MHz. The present work demonstrates that phase contrast imaging can accurately measure ultrasonic fields with frequencies up to 20 MHz and pressure amplitudes near 10 kPa. Accurate measurements at high ultrasonic frequencies are performed by tailoring the measurement conditions to limit optical diffraction as guided by a simple dimensionless parameter. In some situations, differences between high frequency measurements made with the phase contrast method and a calibrated hydrophone become apparent, and the reasons for these differences are discussed. Extending optical imaging measurements to high ultrasonic frequencies could facilitate quantitative applications of ultrasound measurements in nondestructive testing and medical therapeutics and diagnostics such as photoacoustic imaging.
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Affiliation(s)
- Aaron M Goldfain
- Applied Physics Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - Christopher S Yung
- Applied Physics Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - Kimberly A Briggman
- Applied Physics Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - Jeeseong Hwang
- Applied Physics Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA
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Yang F, Song W, Zhang C, Fang H, Min C, Yuan X. A Phase-Shifted Surface Plasmon Resonance Sensor for Simultaneous Photoacoustic Volumetric Imaging and Spectroscopic Analysis. ACS Sens 2021; 6:1840-1848. [PMID: 33861572 DOI: 10.1021/acssensors.1c00029] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
For biomedical photoacoustic applications, an ongoing challenge in simultaneous volumetric imaging and spectroscopic analysis arises from ultrasonic detectors lacking high sensitivity to pressure transients over a broad spectral bandwidth. Photoacoustic impulses can be measured on the basis of the ultrafast temporal dynamics and highly sensitive response of surface plasmon polaritons to the refractive index changes. Taking advantage of the ultra-sensitive phase shift of surface plasmons caused by ultrasonic perturbations instead of the reflectivity change [as is the case for traditional surface plasmon resonance (SPR) sensors], a novel SPR sensor based on phase-shifted interrogation was developed for the broadband measurement of photoacoustically induced pressure transients with improved detection sensitivity. Specifically, by encoding the acoustically modulated phase change into time-varying interference intensity, our sensor achieved an almost five-fold sensitivity enhancement (∼98 Pa noise-equivalent pressure) compared with the reflectivity-mode SPR sensing technologies (∼470 Pa) while retaining a broadband acoustic response of ∼174 MHz. Incorporating our sensor into an optical-resolution photoacoustic microscope, we performed label-free imaging of a zebrafish eye in vivo, enabling simultaneous volumetric visualization and spectrally resolved discrimination of anatomical features. This novel sensing technology has potential for advancing biomedical ultrasonic and/or photoacoustic investigations.
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Affiliation(s)
- Fan Yang
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
- Nanophotonics Research Center, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Wei Song
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Chonglei Zhang
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Hui Fang
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Changjun Min
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Xiaocong Yuan
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
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46
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Zhang D, Wang Z, Cheng Z, Zhang W, Yang F, Yang S. An Ellipsoidal Focused Ultrasound Transducer for Extend-focus Photoacoustic Microscopy. IEEE Trans Biomed Eng 2021; 68:3748-3752. [PMID: 33974538 DOI: 10.1109/tbme.2021.3078729] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Limited by spherical focused ultrasound transducer (SUT) with a high acoustic numerical aperture, photoacoustic microscopy (PAM) suffers a rapidly degrading sensitivity and lateral resolution as increased depth. In this study, an ellipsoidal focused ultrasound transducer (EUT) was developed to address the above restriction via providing high sensitivity and lateral resolution over a large depth of field (DOF). METHODS To fabricate the EUT, the piezoelectric element was laminated onto a curved steel surface for self-focusing (the ellipsoidal continuous-focus geometry was employed instead of the spherical single-focus one). Additionally, phantoms and in vivo animal experiments were performed by an extend-focus PAM equipped with EUT to characterize its performance. RESULTS The EUT involved over 30 MHz center frequency and -6 dB bandwidth of 124% with a resolution-invariant focal depth of 1.39 mm, more than 3 times the DOF of the SUT. CONCLUSION The in vivo imaging results demonstrated that the EUT was capable of extending the focal depth to get rid of the restriction of the visual field, while the DOF of the SUT was limited by the nature of spherical geometry. SIGNIFICANCE The EUT markedly enhances the image quality at different imaging depths, which has great potential for promoting the biomedical development of in vivo rapid-noninvasive PAM.
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47
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Wiacek A, Lediju Bell MA. Photoacoustic-guided surgery from head to toe [Invited]. BIOMEDICAL OPTICS EXPRESS 2021; 12:2079-2117. [PMID: 33996218 PMCID: PMC8086464 DOI: 10.1364/boe.417984] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 05/04/2023]
Abstract
Photoacoustic imaging-the combination of optics and acoustics to visualize differences in optical absorption - has recently demonstrated strong viability as a promising method to provide critical guidance of multiple surgeries and procedures. Benefits include its potential to assist with tumor resection, identify hemorrhaged and ablated tissue, visualize metal implants (e.g., needle tips, tool tips, brachytherapy seeds), track catheter tips, and avoid accidental injury to critical subsurface anatomy (e.g., major vessels and nerves hidden by tissue during surgery). These benefits are significant because they reduce surgical error, associated surgery-related complications (e.g., cancer recurrence, paralysis, excessive bleeding), and accidental patient death in the operating room. This invited review covers multiple aspects of the use of photoacoustic imaging to guide both surgical and related non-surgical interventions. Applicable organ systems span structures within the head to contents of the toes, with an eye toward surgical and interventional translation for the benefit of patients and for use in operating rooms and interventional suites worldwide. We additionally include a critical discussion of complete systems and tools needed to maximize the success of surgical and interventional applications of photoacoustic-based technology, spanning light delivery, acoustic detection, and robotic methods. Multiple enabling hardware and software integration components are also discussed, concluding with a summary and future outlook based on the current state of technological developments, recent achievements, and possible new directions.
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Affiliation(s)
- Alycen Wiacek
- Department of Electrical and Computer Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
| | - Muyinatu A. Lediju Bell
- Department of Electrical and Computer Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Biomedical Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Computer Science, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
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48
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Bai X, Li X, Ma J, Guan BO. Improvement in resolution of fiber-laser photoacoustic tomography based on a virtual-point concept. Vis Comput Ind Biomed Art 2021; 4:4. [PMID: 33620595 PMCID: PMC7902747 DOI: 10.1186/s42492-021-00070-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/04/2021] [Indexed: 12/20/2022] Open
Abstract
In this study, a virtual-point concept was introduced into fiber-laser photoacoustic tomography to improve the elevational image resolution. The flexible fiber laser was bent into an arc shape to conform to the ultrasound wavefront, which formed an ultrasound focus at the center of the arc. The synthetic aperture focusing technique was utilized to reconstruct the images; as a result, the elevational resolution particularly within the out-of-focus region was considerably improved compared to the resolution of an image retrieved by multiplexing the PA time-resolved signals with sound velocity. The all-optical fiber-laser photoacoustic tomography system with a high spatial resolution has potential for various applications, including biomedical research and preclinical/clinical diagnosis.
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Affiliation(s)
- Xue Bai
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou, 511443, China
| | - Xu Li
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou, 511443, China
| | - Jun Ma
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou, 511443, China.
| | - Bai-Ou Guan
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou, 511443, China
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Imaging of photoacoustic-mediated permeabilization of giant unilamellar vesicles (GUVs). Sci Rep 2021; 11:2775. [PMID: 33531539 PMCID: PMC7854711 DOI: 10.1038/s41598-021-82140-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 01/13/2021] [Indexed: 01/24/2023] Open
Abstract
Target delivery of large foreign materials to cells requires transient permeabilization of the cell membrane without toxicity. Giant unilamellar vesicles (GUVs) mimic the phospholipid bilayer of the cell membrane and are also useful drug delivery vehicles. Controlled increase of the permeability of GUVs is a delicate balance between sufficient perturbation for the delivery of the GUV contents and damage to the vesicles. Here we show that photoacoustic waves can promote the release of FITC-dextran or GFP from GUVs without damage. Real-time interferometric imaging offers the first movies of photoacoustic wave propagation and interaction with GUVs. The photoacoustic waves are seen as mostly compressive half-cycle pulses with peak pressures of ~ 1 MPa and spatial extent FWHM ~ 36 µm. At a repetition rate of 10 Hz, they enable the release of 25% of the FITC-dextran content of GUVs in 15 min. Such photoacoustic waves may enable non-invasive targeted release of GUVs and cell transfection over large volumes of tissues in just a few minutes.
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50
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Canfield RA, Ahrens J, Bingham J, Fetzer B, Müller-Wirts T, O’Donnell M, Georgeson G, Pelivanov I. Distance and Angle Correction System (DACS) for a kHz A-Scan Rate Pump-Probe Laser-Ultrasound Inspection. SENSORS 2020; 20:s20247266. [PMID: 33352911 PMCID: PMC7766991 DOI: 10.3390/s20247266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 11/16/2022]
Abstract
Non-contact optical detection of ultrasound critically depends on the amount of light collected from the detection surface. Although it can be optimized in multiple ways for an ideal flat polished surface, industrial non-destructive testing and evaluation (NDT&E) usually requires optical detectors to be robust for unpolished material surfaces that are usually rough and curved. Confocal detectors provide the best light collection but must trade off sensitivity with depth of field. Specifically, detection efficiency increases with the numerical aperture (NA) of the detector, but the depth of field drops. Therefore, fast realignment of the detector focal point is critical for in-field applications. Here, we propose an optical distance and angle correction system (DACS) and demonstrate it in a kHz-rate laser-ultrasound inspection system. It incorporates a Sagnac interferometer on receive for the fast scanning of aircraft composites, which minimizes the required initial alignment. We show that DACS performs stably for different composite surfaces while providing ±2° angular and ±2 mm axial automatic correction with a maximum 100 ms realignment time.
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Affiliation(s)
- Ryan A. Canfield
- Department of Bioengineering, University of Washington, Box 355061, Seattle, WA 98195, USA; (R.A.C.); (M.O.)
| | - Jan Ahrens
- TEM Messtechnik GmbH, Großer Hillen 38, D-30559 Hannover, Germany; (J.A.); (T.M.-W.)
| | - Jill Bingham
- Boeing Research and Technology, 9725 E Marginal Way S, Tukwila, WA 98108, USA; (J.B.); (B.F.); (G.G.)
| | - Barry Fetzer
- Boeing Research and Technology, 9725 E Marginal Way S, Tukwila, WA 98108, USA; (J.B.); (B.F.); (G.G.)
| | - Thomas Müller-Wirts
- TEM Messtechnik GmbH, Großer Hillen 38, D-30559 Hannover, Germany; (J.A.); (T.M.-W.)
| | - Matthew O’Donnell
- Department of Bioengineering, University of Washington, Box 355061, Seattle, WA 98195, USA; (R.A.C.); (M.O.)
| | - Gary Georgeson
- Boeing Research and Technology, 9725 E Marginal Way S, Tukwila, WA 98108, USA; (J.B.); (B.F.); (G.G.)
| | - Ivan Pelivanov
- Department of Bioengineering, University of Washington, Box 355061, Seattle, WA 98195, USA; (R.A.C.); (M.O.)
- Correspondence: ; Tel.: +1-206-221-8330
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