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Li B, Lu M, Zhou T, Bu M, Gu W, Wang J, Zhu Q, Liu X, Ta D. Removing Artifacts in Transcranial Photoacoustic Imaging With Polarized Self-Attention Dense-UNet. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:1530-1543. [PMID: 39013725 DOI: 10.1016/j.ultrasmedbio.2024.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 05/28/2024] [Accepted: 06/16/2024] [Indexed: 07/18/2024]
Abstract
OBJECTIVE Photoacoustic imaging (PAI) is a promising transcranial imaging technique. However, the distortion of photoacoustic signals induced by the skull significantly influences its imaging quality. We aimed to use deep learning for removing artifacts in PAI. METHODS In this study, we propose a polarized self-attention dense U-Net, termed PSAD-UNet, to correct the distortion and accurately recover imaged objects beneath bone plates. To evaluate the performance of the proposed method, a series of experiments was performed using a custom-built PAI system. RESULTS The experimental results showed that the proposed PSAD-UNet method could effectively implement transcranial PAI through a one- or two-layer bone plate. Compared with the conventional delay-and-sum and classical U-Net methods, PSAD-UNet can diminish the influence of bone plates and provide high-quality PAI results in terms of structural similarity and peak signal-to-noise ratio. The 3-D experimental results further confirm the feasibility of PSAD-UNet in 3-D transcranial imaging. CONCLUSION PSAD-UNet paves the way for implementing transcranial PAI with high imaging accuracy, which reveals broad application prospects in preclinical and clinical fields.
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Affiliation(s)
- Boyi Li
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China
| | - Mengyang Lu
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China
| | - Tianhua Zhou
- Department of Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China
| | - Mengxu Bu
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China
| | - Wenting Gu
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China
| | - Junyi Wang
- Department of Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China
| | - Qiuchen Zhu
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China
| | - Xin Liu
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China.
| | - Dean Ta
- Academy for Engineering and Technology, Fudan University, Shanghai 200438, China; Department of Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China
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Yang X, Chai C, Chen YH, Sawan M. Optical Transmission in Single-Layer Brain Tissues under Different Optical Source Types: Modelling and Simulation. Bioengineering (Basel) 2024; 11:916. [PMID: 39329658 PMCID: PMC11428375 DOI: 10.3390/bioengineering11090916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2024] [Revised: 09/03/2024] [Accepted: 09/11/2024] [Indexed: 09/28/2024] Open
Abstract
The human brain is a complex organ controlling daily activity. Present technique models have mostly focused on multi-layer brain tissues, which lack understanding of the propagation characteristics of various single brain tissues. To better understand the influence of different optical source types on individual brain tissues, we constructed single-layer brain models and simulated optical propagation using the Monte Carlo method. Based on the optical simulation results, sixteen optical source types had different optical energy distributions, and the distribution in cerebrospinal fluid had obvious characteristics. Five brain tissues (scalp, skull, cerebrospinal fluid, gray matter, and blood vessel) had the same set of the first three optical source types with maximum depth, while white matter had a different set of the first three optical source types with maximum depth. Each brain tissue had different optical source types with the maximum and minimum full width at half maximum. The study on single-layer brain tissues under different optical source types lays the foundation for constructing complex brain models with multiple tissue layers. It provides a theoretical reference for optimizing the selection of optical source devices for brain imaging.
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Affiliation(s)
- Xi Yang
- CenBRAIN Neurotech Center of Excellence, School of Engineering, Westlake University, 600 Dunyu Road, Xihu District, Hangzhou 310030, China; (X.Y.); (C.C.)
- Institute of Advanced Technology, Westlake Institute for Advanced Study, 18 Shilongshan Street, Xihu District, Hangzhou 310024, China
| | - Chengpeng Chai
- CenBRAIN Neurotech Center of Excellence, School of Engineering, Westlake University, 600 Dunyu Road, Xihu District, Hangzhou 310030, China; (X.Y.); (C.C.)
- Institute of Advanced Technology, Westlake Institute for Advanced Study, 18 Shilongshan Street, Xihu District, Hangzhou 310024, China
| | - Yun-Hsuan Chen
- CenBRAIN Neurotech Center of Excellence, School of Engineering, Westlake University, 600 Dunyu Road, Xihu District, Hangzhou 310030, China; (X.Y.); (C.C.)
- Institute of Advanced Technology, Westlake Institute for Advanced Study, 18 Shilongshan Street, Xihu District, Hangzhou 310024, China
| | - Mohamad Sawan
- CenBRAIN Neurotech Center of Excellence, School of Engineering, Westlake University, 600 Dunyu Road, Xihu District, Hangzhou 310030, China; (X.Y.); (C.C.)
- Institute of Advanced Technology, Westlake Institute for Advanced Study, 18 Shilongshan Street, Xihu District, Hangzhou 310024, China
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Slobodkin Y, Katz O. Computational wave-based photoacoustic imaging through an unknown thick aberrating layer. PHOTOACOUSTICS 2024; 36:100584. [PMID: 38322618 PMCID: PMC10844652 DOI: 10.1016/j.pacs.2024.100584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 02/08/2024]
Abstract
We introduce a physics-based computational reconstruction framework for non-invasive photoacoustic tomography through a thick aberrating layer. Our wave-based approach leverages an analytic formulation of diffraction to beamform a photoacoustic image, when the aberrating layer profile is known. When the profile of the aberrating layer is unknown, the same analytical formulation serves as the basis for an automatic-differentiation regularized optimization algorithm that simultaneously reconstructs both the profile of the aberrating layer and the optically absorbing targets. Results from numerical studies and proof-of-concept experiments show promise for fast beamforming that takes into account diffraction effects occurring in the propagation through thick, highly-aberrating layers.
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Affiliation(s)
- Yevgeny Slobodkin
- Institute of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Ori Katz
- Institute of Applied Physics, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
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Eleni Karakatsani M, Estrada H, Chen Z, Shoham S, Deán-Ben XL, Razansky D. Shedding light on ultrasound in action: Optical and optoacoustic monitoring of ultrasound brain interventions. Adv Drug Deliv Rev 2024; 205:115177. [PMID: 38184194 PMCID: PMC11298795 DOI: 10.1016/j.addr.2023.115177] [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] [Received: 10/09/2023] [Revised: 12/27/2023] [Accepted: 12/31/2023] [Indexed: 01/08/2024]
Abstract
Monitoring brain responses to ultrasonic interventions is becoming an important pillar of a growing number of applications employing acoustic waves to actuate and cure the brain. Optical interrogation of living tissues provides a unique means for retrieving functional and molecular information related to brain activity and disease-specific biomarkers. The hybrid optoacoustic imaging methods have further enabled deep-tissue imaging with optical contrast at high spatial and temporal resolution. The marriage between light and sound thus brings together the highly complementary advantages of both modalities toward high precision interrogation, stimulation, and therapy of the brain with strong impact in the fields of ultrasound neuromodulation, gene and drug delivery, or noninvasive treatments of neurological and neurodegenerative disorders. In this review, we elaborate on current advances in optical and optoacoustic monitoring of ultrasound interventions. We describe the main principles and mechanisms underlying each method before diving into the corresponding biomedical applications. We identify areas of improvement as well as promising approaches with clinical translation potential.
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Affiliation(s)
- Maria Eleni Karakatsani
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland; Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Héctor Estrada
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland; Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Zhenyue Chen
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland; Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Shy Shoham
- Department of Ophthalmology and Tech4Health and Neuroscience Institutes, NYU Langone Health, NY, USA
| | - Xosé Luís Deán-Ben
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland; Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland.
| | - Daniel Razansky
- Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, University of Zurich, Switzerland; Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland.
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Huang B, Wong TTW. Review of low-cost light sources and miniaturized designs in photoacoustic microscopy. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:S11503. [PMID: 37869479 PMCID: PMC10587694 DOI: 10.1117/1.jbo.29.s1.s11503] [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: 08/29/2023] [Revised: 10/02/2023] [Accepted: 10/09/2023] [Indexed: 10/24/2023]
Abstract
Significance Photoacoustic microscopy (PAM) is a promising imaging technique to provide structural, functional, and molecular information for preclinical and clinical studies. However, expensive and bulky lasers and motorized stages have limited the broad applications of conventional PAM systems. A recent trend is to use low-cost light sources and miniaturized designs to develop a compact PAM system and expand its applications from benchtop to bedside. Aim We provide (1) an overview of PAM systems and their limitations, (2) a comprehensive review of PAM systems with low-cost light sources and their applications, (3) a comprehensive review of PAM systems with miniaturized and handheld scanning designs, and (4) perspective applications and a summary of the cost-effective and miniaturized PAM systems. Approach Papers published before July 2023 in the area of using low-cost light sources and miniaturized designs in PAM were reviewed. They were categorized into two main parts: (1) low-cost light sources and (2) miniaturized or handheld designs. The first part was classified into two subtypes: pulsed laser diode and continuous-wave laser diode. The second part was also classified into two subtypes: galvanometer scanner and micro-electro-mechanical system scanner. Results Significant progress has been made in the development of PAM systems based on low-cost and compact light sources as well as miniaturized and handheld designs. Conclusions The review highlights the potential of these advancements to revolutionize PAM technology, making it more accessible and practical for various applications in preclinical studies, clinical practice, and long-term monitoring.
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Affiliation(s)
- Bingxin Huang
- Hong Kong University of Science and Technology, Department of Chemical and Biological Engineering, Translational and Advanced Bioimaging Laboratory, Hong Kong, China
| | - Terence T. W. Wong
- Hong Kong University of Science and Technology, Department of Chemical and Biological Engineering, Translational and Advanced Bioimaging Laboratory, Hong Kong, China
- Hong Kong University of Science and Technology, Research Center for Medical Imaging and Analysis, Hong Kong, China
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Wang R, Zhu J, Meng Y, Wang X, Chen R, Wang K, Li C, Shi J. Adaptive machine learning method for photoacoustic computed tomography based on sparse array sensor data. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 242:107822. [PMID: 37832425 DOI: 10.1016/j.cmpb.2023.107822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 08/18/2023] [Accepted: 09/17/2023] [Indexed: 10/15/2023]
Abstract
BACKGROUND AND OBJECTIVE Photoacoustic computed tomography (PACT) is a non-invasive biomedical imaging technology that has developed rapidly in recent decades, especially has shown potential for small animal studies and early diagnosis of human diseases. To obtain high-quality images, the photoacoustic imaging system needs a high-element-density detector array. However, in practical applications, due to the cost limitation, manufacturing technology, and the system requirement in miniaturization and robustness, it is challenging to achieve sufficient elements and high-quality reconstructed images, which may even suffer from artifacts. Different from the latest machine learning methods based on removing distortions and artifacts to recover high-quality images, this paper proposes an adaptive machine learning method to firstly predict and complement the photoacoustic sensor channel data from sparse array sampling and then reconstruct images through conventional reconstruction algorithms. METHODS We develop an adaptive machine learning method to predict and complement the photoacoustic sensor channel data. The model consists of XGBoost and a neural network named SS-net. To handle data sets of different sizes and improve the generalization, a tunable parameter is used to control the weights of XGBoost and SS-net outputs. RESULTS The proposed method achieved superior performance as demonstrated by simulation, phantom experiments, and in vivo experiment results. Compared with linear interpolation, XGBoost, CAE, and U-net, the simulation results show that the SSIM value is increased by 12.83%, 6.78%, 21.46%, and 12.33%. Moreover, the median R2 is increased by 34.4%, 8.1%, 28.6%, and 84.1% with the in vivo data. CONCLUSIONS This model provides a framework to predict the missed photoacoustic sensor data on a sparse ring-shaped array for PACT imaging and has achieved considerable improvements in reconstructing the objects. Compared with linear interpolation and other deep learning methods qualitatively and quantitatively, our proposed methods can effectively suppress artifacts and improve image quality. The advantage of our methods is that there is no need for preparing a large number of images as the training dataset, and the data for training is directly from the sensors. It has the potential to be applied to a wide range of photoacoustic imaging detector arrays for low-cost and user-friendly clinical applications.
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Affiliation(s)
| | - Jing Zhu
- Zhejiang Lab, Hangzhou 311100, China
| | | | | | | | | | - Chiye Li
- Zhejiang Lab, Hangzhou 311100, China; Research Center for Humanoid Sensing, Zhejiang Lab, Hangzhou 311100, China.
| | - Junhui Shi
- Zhejiang Lab, Hangzhou 311100, China; Research Center for Humanoid Sensing, Zhejiang Lab, Hangzhou 311100, China.
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Xu S, Momin M, Ahmed S, Hossain A, Veeramuthu L, Pandiyan A, Kuo CC, Zhou T. Illuminating the Brain: Advances and Perspectives in Optoelectronics for Neural Activity Monitoring and Modulation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2303267. [PMID: 37726261 DOI: 10.1002/adma.202303267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/30/2023] [Indexed: 09/21/2023]
Abstract
Optogenetic modulation of brain neural activity that combines optical and electrical modes in a unitary neural system has recently gained robust momentum. Controlling illumination spatial coverage, designing light-activated modulators, and developing wireless light delivery and data transmission are crucial for maximizing the use of optical neuromodulation. To this end, biocompatible electrodes with enhanced optoelectrical performance, device integration for multiplexed addressing, wireless transmission, and multimodal operation in soft systems have been developed. This review provides an outlook for uniformly illuminating large brain areas while spatiotemporally imaging the neural responses upon optoelectrical stimulation with little artifacts. Representative concepts and important breakthroughs, such as head-mounted illumination, multiple implanted optical fibers, and micro-light-delivery devices, are discussed. Examples of techniques that incorporate electrophysiological monitoring and optoelectrical stimulation are presented. Challenges and perspectives are posed for further research efforts toward high-density optoelectrical neural interface modulation, with the potential for nonpharmacological neurological disease treatments and wireless optoelectrical stimulation.
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Affiliation(s)
- Shumao Xu
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Marzia Momin
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Salahuddin Ahmed
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Arafat Hossain
- Department of Electrical Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Loganathan Veeramuthu
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Archana Pandiyan
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Chi-Ching Kuo
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Tao Zhou
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
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Kirchner T, Villringer C, Laufer J. Evaluation of ultrasound sensors for transcranial photoacoustic sensing and imaging. PHOTOACOUSTICS 2023; 33:100556. [PMID: 38021292 PMCID: PMC10658602 DOI: 10.1016/j.pacs.2023.100556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 12/01/2023]
Abstract
Photoacoustic imaging through skull bone causes strong attenuation and distortion of the acoustic wavefront, which diminishes image contrast and resolution. As a result, transcranial photoacoustic measurements in humans have been challenging to demonstrate. In this study, we investigated the acoustic transmission through the human skull to design an ultrasound sensor suitable for transcranial PA imaging and sensing. We measured the frequency dependent losses of human cranial bones ex vivo, compared the performance of a range of piezoelectric and optical ultrasound sensors, and imaged skull phantoms using a PA tomograph based on a planar Fabry-Perot sensor. All transcranial photoacoustic measurements show the typical effects of frequency and thickness dependent attenuation and aberration associated with acoustic propagation through bone. The performance of plano-concave optical resonator ultrasound sensors was found to be highly suitable for transcranial photoacoustic measurements.
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Affiliation(s)
- Thomas Kirchner
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120 Halle (Saale), Germany
| | - Claus Villringer
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120 Halle (Saale), Germany
- Technische Hochschule Wildau, Hochschulring 1, 15745 Wildau, Germany
| | - Jan Laufer
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120 Halle (Saale), Germany
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Noltes ME, Bader M, Metman MJH, Vonk J, Steinkamp PJ, Kukačka J, Westerlaan HE, Dierckx RAJO, van Hemel BM, Brouwers AH, van Dam GM, Jüstel D, Ntziachristos V, Kruijff S. Towards in vivo characterization of thyroid nodules suspicious for malignancy using multispectral optoacoustic tomography. Eur J Nucl Med Mol Imaging 2023; 50:2736-2750. [PMID: 37039901 PMCID: PMC10317911 DOI: 10.1007/s00259-023-06189-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 03/05/2023] [Indexed: 04/12/2023]
Abstract
PURPOSE Patient-tailored management of thyroid nodules requires improved risk of malignancy stratification by accurate preoperative nodule assessment, aiming to personalize decisions concerning diagnostics and treatment. Here, we perform an exploratory pilot study to identify possible patterns on multispectral optoacoustic tomography (MSOT) for thyroid malignancy stratification. For the first time, we directly correlate MSOT images with histopathology data on a detailed level. METHODS We use recently enhanced data processing and image reconstruction methods for MSOT to provide next-level image quality by means of improved spatial resolution and spectral contrast. We examine optoacoustic features in thyroid nodules associated with vascular patterns and correlate these directly with reference histopathology. RESULTS Our methods show the ability to resolve blood vessels with diameters of 250 μm at depths of up to 2 cm. The vessel diameters derived on MSOT showed an excellent correlation (R2-score of 0.9426) with the vessel diameters on histopathology. Subsequently, we identify features of malignancy observable in MSOT, such as intranodular microvascularity and extrathyroidal extension verified by histopathology. Despite these promising features in selected patients, we could not determine statistically relevant differences between benign and malignant thyroid nodules based on mean oxygen saturation in thyroid nodules. Thus, we illustrate general imaging artifacts of the whole field of optoacoustic imaging that reduce image fidelity and distort spectral contrast, which impedes quantification of chromophore presence based on mean concentrations. CONCLUSION We recommend examining optoacoustic features in addition to chromophore quantification to rank malignancy risk. We present optoacoustic images of thyroid nodules with the highest spatial resolution and spectral contrast to date, directly correlated to histopathology, pushing the clinical translation of MSOT.
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Affiliation(s)
- Milou E Noltes
- Department of Surgical Oncology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Maximilian Bader
- 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
| | - Madelon J H Metman
- Department of Surgical Oncology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Jasper Vonk
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Pieter J Steinkamp
- Department of Surgical Oncology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Jan Kukačka
- 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
| | - Henriette E Westerlaan
- Department of Radiology, University Medical Center Groningen, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Rudi A J O Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bettien M van Hemel
- Department of Pathology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Adrienne H Brouwers
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Gooitzen M van Dam
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- AxelaRx/TRACER Europe BV, Groningen, the Netherlands
| | - Dominik Jüstel
- 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
- Institute of Computational Biology, 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
- Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich, Munich, Germany
| | - Schelto Kruijff
- Department of Surgical Oncology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
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10
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Cao R, Luo Y, Xu J, Luo X, Geng K, Aborahama Y, Cui M, Davis S, Na S, Tong X, Liu C, Sastry K, Maslov K, Hu P, Zhang Y, Lin L, Zhang Y, Wang LV. Single-shot 3D photoacoustic computed tomography with a densely packed array for transcranial functional imaging. ARXIV 2023:arXiv:2306.14471v1. [PMID: 37426449 PMCID: PMC10327245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Photoacoustic computed tomography (PACT) is emerging as a new technique for functional brain imaging, primarily due to its capabilities in label-free hemodynamic imaging. Despite its potential, the transcranial application of PACT has encountered hurdles, such as acoustic attenuations and distortions by the skull and limited light penetration through the skull. To overcome these challenges, we have engineered a PACT system that features a densely packed hemispherical ultrasonic transducer array with 3072 channels, operating at a central frequency of 1 MHz. This system allows for single-shot 3D imaging at a rate equal to the laser repetition rate, such as 20 Hz. We have achieved a single-shot light penetration depth of approximately 9 cm in chicken breast tissue utilizing a 750 nm laser (withstanding 3295-fold light attenuation and still retaining an SNR of 74) and successfully performed transcranial imaging through an ex vivo human skull using a 1064 nm laser. Moreover, we have proven the capacity of our system to perform single-shot 3D PACT imaging in both tissue phantoms and human subjects. These results suggest that our PACT system is poised to unlock potential for real-time, in vivo transcranial functional imaging in humans.
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Affiliation(s)
- Rui Cao
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Yilin Luo
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Jinhua Xu
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Xiaofei Luo
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Ku Geng
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Yousuf Aborahama
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Manxiu Cui
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Samuel Davis
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Shuai Na
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Xin Tong
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Cindy Liu
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Karteek Sastry
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Konstantin Maslov
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Peng Hu
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Yide Zhang
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Li Lin
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Yang Zhang
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Lihong V. Wang
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
- Caltech Optical Imaging Laboratory, Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA
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11
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Gonzalez EA, Bell MAL. Photoacoustic Imaging and Characterization of Bone in Medicine: Overview, Applications, and Outlook. Annu Rev Biomed Eng 2023; 25:207-232. [PMID: 37000966 DOI: 10.1146/annurev-bioeng-081622-025405] [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: 11/19/2023]
Abstract
Photoacoustic techniques have shown promise in identifying molecular changes in bone tissue and visualizing tissue microstructure. This capability represents significant advantages over gold standards (i.e., dual-energy X-ray absorptiometry) for bone evaluation without requiring ionizing radiation. Instead, photoacoustic imaging uses light to penetrate through bone, followed by acoustic pressure generation, resulting in highly sensitive optical absorption contrast in deep biological tissues. This review covers multiple bone-related photoacoustic imaging contributions to clinical applications, spanning bone cancer, joint pathologies, spinal disorders, osteoporosis, bone-related surgical guidance, consolidation monitoring, and transsphenoidal and transcranial imaging. We also present a summary of photoacoustic-based techniques for characterizing biomechanical properties of bone, including temperature, guided waves, spectral parameters, and spectroscopy. We conclude with a future outlook based on the current state of technological developments, recent achievements, and possible new directions.
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Affiliation(s)
- Eduardo A Gonzalez
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Muyinatu A Lediju Bell
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Electrical and Computer Engineering and Department of Computer Science, Johns Hopkins University, Baltimore, Maryland, USA;
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12
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Zhang F, Zhang J, Shen Y, Gao Z, Yang C, Liang M, Gao F, Liu L, Zhao H, Gao F. Photoacoustic digital brain and deep-learning-assisted image reconstruction. PHOTOACOUSTICS 2023; 31:100517. [PMID: 37292518 PMCID: PMC10244697 DOI: 10.1016/j.pacs.2023.100517] [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: 04/13/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/10/2023]
Abstract
Photoacoustic tomography (PAT) is a newly developed medical imaging modality, which combines the advantages of pure optical imaging and ultrasound imaging, owning both high optical contrast and deep penetration depth. Very recently, PAT is studied in human brain imaging. Nevertheless, while ultrasound waves are passing through the human skull tissues, the strong acoustic attenuation and aberration will happen, which causes photoacoustic signals' distortion. In this work, we use 180 T1 weighted magnetic resonance imaging (MRI) human brain volumes along with the corresponding magnetic resonance angiography (MRA) brain volumes, and segment them to generate the 2D human brain numerical phantoms for PAT. The numerical phantoms contain six kinds of tissues, which are scalp, skull, white matter, gray matter, blood vessel and cerebrospinal fluid. For every numerical phantom, Monte-Carlo based optical simulation is deployed to obtain the photoacoustic initial pressure based on optical properties of human brain. Then, two different k-wave models are used for the skull-involved acoustic simulation, which are fluid media model and viscoelastic media model. The former one only considers longitudinal wave propagation, and the latter model takes shear wave into consideration. Then, the PA sinograms with skull-induced aberration is taken as the input of U-net, and the skull-stripped ones are regarded as the supervision of U-net to train the network. Experimental result shows that the skull's acoustic aberration can be effectively alleviated after U-net correction, achieving conspicuous improvement in quality of PAT human brain images reconstructed from the corrected PA signals, which can clearly show the cerebral artery distribution inside the human skull.
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Affiliation(s)
- Fan Zhang
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Jiadong Zhang
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yuting Shen
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zijian Gao
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Changchun Yang
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Mingtao Liang
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Feng Gao
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Li Liu
- Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Hulin Zhao
- Department of Neural Surgery, Chinese PLA General Hospital, Beijing, China
| | - Fei Gao
- Hybrid Imaging System Laboratory, School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Shanghai Engineering Research Center of Intelligent Vision and Imaging, Shanghai 201210, China
- Shanghai Clinical Research and Trial Center, Shanghai 201210, China
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13
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Luo X, Jiang J, Wu H, Li M, Wang B. The influences of finite aperture size in photoacoustic computed tomography. ULTRASONICS 2023; 133:107042. [PMID: 37186987 DOI: 10.1016/j.ultras.2023.107042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 04/12/2023] [Accepted: 05/08/2023] [Indexed: 05/17/2023]
Abstract
In photoacoustic computed tomography (PACT), the "finite aperture effect" is often characterized as a tangential resolution that increases proportionally with the distance from the rotation center. However, this conclusion is based on the inaccurate point-detector assumption used in image reconstruction. In this study, we appropriately modeled the finite size of the acoustic detector in the back-projection (BP) based image reconstruction to improve the accuracy of the time delay calculation and systematically investigated its effects. Our results showed that the main effect of the finite aperture size is the creation of a limited high-quality imaging region (HQIR) around the scanning center, due to the directional sensitivity of the detector. We also demonstrated that the "finite aperture effect" can reduce the optimal number of detectors required for spatial anti-aliasing. These new findings provide novel perspectives for optimizing PACT systems and corresponding reconstruction methods.
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Affiliation(s)
- Xiaofei Luo
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410083, China
| | - Jinsheng Jiang
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410083, China
| | - Hualin Wu
- College of Mechanical and Electrical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Minhao Li
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410083, China
| | - Bo Wang
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410083, China.
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14
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Salih AK, ALWAN AH, Opulencia MJC, Uinarni H, Khamidova FM, Atiyah MS, Awadh SA, Hammid AT, Arzehgar Z. Evaluation of Cholesterol Thickness of Blood Vessels Using Photoacoustic Technology. BIOMED RESEARCH INTERNATIONAL 2023; 2023:2721427. [PMID: 37090193 PMCID: PMC10115531 DOI: 10.1155/2023/2721427] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 06/05/2022] [Accepted: 06/24/2022] [Indexed: 04/25/2023]
Abstract
One of the primary indicators of plaque vulnerability is the lipid composition of atherosclerotic plaques. Therefore, the medical industry requires a method to evaluate necrotic nuclei in atherosclerosis imaging with sensitivity. In this regard, photoacoustic imaging is a plaque detection method that provides chemical information on lipids and cholesterol thickness in the arterial walls of the patient. This aspect aims to increase the low-frequency axial resolution by developing a new photoacoustic-based system. A photoacoustic system has been developed to detect the cholesterol thickness of the blood vessels to observe the progression of plaque in the heart's blood vessels. The application of the coherent photoacoustic discontinuous correlation tomography technique, which is based on a novel signal processing, significantly increased the cholesterol oleate's sensitivity to plaque necrosis. By enhancing the quality of thickness detection, the system for measuring the thickness of cholesterol in blood vessels has been reduced to approximately 23 microns. The results show that the phase spectrum peaked at 100 Hz at 58.66 degrees, and at 400 Hz, the phase spectrum was 46.37 degrees. The minimum amplitude is 1.95 at 100 Hz and 17.67 at 400 Hz. In conclusion, it can be stated that photoacoustic imaging as a method based on new technologies is of great importance in medical research, which is based on the use of nonionizing radiation to perform diagnostic processes and measure different types of body tissues.
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Affiliation(s)
| | - Ala Hadi ALWAN
- Ibn Al-Bitar Specialized Center for Cardiac Surgery, Baghdad, Iraq
| | | | - Herlina Uinarni
- Atma Jaya Catholic University of Indonesia, Jakarta, Indonesia
- Pantai Indah Kapuk Hospital, North Jakarta, Indonesia
| | - Firuza M. Khamidova
- Department of Ophthalmology, Samarkand State Medical Institute, Samarkand, Uzbekistan
- Tashkent State Dental Institute, Tashkent, Uzbekistan
| | | | | | | | - Zeinab Arzehgar
- Department of Chemistry, Payame Noor University, Tehran, Iran
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15
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Ni R, Deán-Ben XL, Treyer V, Gietl A, Hock C, Klohs J, Nitsch RM, Razansky D. Coregistered transcranial optoacoustic and magnetic resonance angiography of the human brain. OPTICS LETTERS 2023; 48:648-651. [PMID: 36723554 DOI: 10.1364/ol.475578] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 12/17/2022] [Indexed: 06/18/2023]
Abstract
Imaging modalities capable of visualizing the human brain have led to major advances in neurology and brain research. Multi-spectral optoacoustic tomography (MSOT) has gained importance for studying cerebral function in rodent models due to its unique capability to map changes in multiple hemodynamic parameters and to directly visualize neural activity within the brain. The technique further provides molecular imaging capabilities that can facilitate early disease diagnosis and treatment monitoring. However, transcranial imaging of the human brain is hampered by acoustic attenuation and other distortions introduced by the skull. Here, we demonstrate non-invasive transcranial MSOT angiography of pial veins through the temporal bone of an adult healthy volunteer. Time-of-flight (TOF) magnetic resonance angiography (MRA) and T1-weighted structural magnetic resonance imaging (MRI) were further acquired to facilitate anatomical registration and interpretation. The superior middle cerebral vein in the temporal cortex was identified in the MSOT images, matching its location observed in the TOF-MRA images. These initial results pave the way toward the application of MSOT in clinical brain imaging.
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16
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Choi W, Park B, Choi S, Oh D, Kim J, Kim C. Recent Advances in Contrast-Enhanced Photoacoustic Imaging: Overcoming the Physical and Practical Challenges. Chem Rev 2023. [PMID: 36642892 DOI: 10.1021/acs.chemrev.2c00627] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
For decades now, photoacoustic imaging (PAI) has been investigated to realize its potential as a niche biomedical imaging modality. Despite its highly desirable optical contrast and ultrasonic spatiotemporal resolution, PAI is challenged by such physical limitations as a low signal-to-noise ratio (SNR), diminished image contrast due to strong optical attenuation, and a lower-bound on spatial resolution in deep tissue. In addition, contrast-enhanced PAI has faced practical limitations such as insufficient cell-specific targeting due to low delivery efficiency and difficulties in developing clinically translatable agents. Identifying these limitations is essential to the continuing expansion of the field, and substantial advances in developing contrast-enhancing agents, complemented by high-performance image acquisition systems, have synergistically dealt with the challenges of conventional PAI. This review covers the past four years of research on pushing the physical and practical challenges of PAI in terms of SNR/contrast, spatial resolution, targeted delivery, and clinical application. Promising strategies for dealing with each challenge are reviewed in detail, and future research directions for next generation contrast-enhanced PAI are discussed.
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Affiliation(s)
- Wonseok Choi
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
| | - Byullee Park
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
| | - Seongwook Choi
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
| | - Donghyeon Oh
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
| | - Jongbeom Kim
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
| | - Chulhong Kim
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and Medical Science and Engineering, Graduate School of Artificial Intelligence, and Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang37673, Republic of Korea
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17
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Tong G, Luzgin A, Xia J, Xu L, Zhang H, Dong C, Wu Z, Wu J, Zhang Y, Qin P. Improved photoacoustic images via wavefront shaping modulation based on the scattering structure. OPTICS EXPRESS 2022; 30:36489-36499. [PMID: 36258576 DOI: 10.1364/oe.470330] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/04/2022] [Indexed: 06/16/2023]
Abstract
Multispectral optoacoustic tomography (MSOT) has become the dominant technical solution for photoacoustic imaging (PAI). However, the laser source of fiber output in the current MSOT method is typically a TEM00 Gaussian beam, which is prone to artifacts and incomplete due to the uneven distribution of the irradiated light intensity. Here, we propose a novel method to improve the quality of photoacoustic image reconstruction by modulating the wavefront shaping of the incident laser beam based on the designed scattering structure. In the experiment, we add the designed scattering structure to the current hemispherical photoacoustic transducer array device. Through experiments and simulations, we investigate and compare the effects of different scattering structures on laser intensity modulation. The results show that an ED1-C20 diffusion structure with a scattering angle of 20 degrees has the most effective modulation of the beam intensity distribution. And we choose gold nanoparticles of 50-100 nanometers (nm) diameters and index finger capillary vessels respectively as the medium of PAI. We obtain the highest ratio of PAI area increases of gold nanoparticles and index finger to devices compare without scattering structure is 29.69% and 634.94%, respectively. Experimental results demonstrate that our method is significantly higher quality than traditional methods, which has great potential for theoretical application in medical PAI.
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18
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Na S, Zhang Y, Wang LV. Cross-Ray Ultrasound Tomography and Photoacoustic Tomography of Cerebral Hemodynamics in Rodents. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201104. [PMID: 35818697 PMCID: PMC9443457 DOI: 10.1002/advs.202201104] [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: 02/24/2022] [Revised: 06/08/2022] [Indexed: 06/15/2023]
Abstract
Recent advances in functional ultrasound imaging (fUS) and photoacoustic tomography (PAT) offer powerful tools for studying brain function. Complementing each other, fUS and PAT, respectively, measure the cerebral blood flow (CBF) and hemoglobin concentrations, allowing synergistic characterization of cerebral hemodynamics. Here, cross-ray ultrasound tomography (CRUST) and its combination with PAT are presented. CRUST employs a virtual point source from a spherically focused ultrasonic transducer (SFUST) to provide widefield excitation at a 4-kHz pulse repetition frequency. A full-ring-shaped ultrasonic transducer array whose imaging plane is orthogonal to the SFUST's acoustic axis receives scattered ultrasonic waves. Superior to conventional fUS, whose sensitivity to blood flow is angle-dependent and low for perpendicular flow, the crossed transmission and panoramic detection fields of CRUST provide omnidirectional sensitivity to CBF. Using CRUST-PAT, the CBF, oxygen saturation, and hemoglobin concentration changes of the mouse brain during sensory stimulation are measured, with a field of view of ≈7 mm in diameter, spatial resolution of ≈170 µm, and temporal resolution of 200 Hz. The results demonstrate CRUST-PAT as a unique tool for studying cerebral hemodynamics.
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Affiliation(s)
- Shuai Na
- Caltech Optical Imaging LaboratoryAndrew and Peggy Cherng Department of Medical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
- Present address:
National Biomedical Imaging Center, College of Future TechnologyPeking UniversityBeijing100871China
| | - Yang Zhang
- Caltech Optical Imaging LaboratoryAndrew and Peggy Cherng Department of Medical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
| | - Lihong V. Wang
- Caltech Optical Imaging LaboratoryAndrew and Peggy Cherng Department of Medical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
- Department of Electrical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
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19
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Marchenko Green’s Function Retrieval in Layered Elastic Media from Two-Sided Reflection and Transmission Data. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12157824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
By solving a Marchenko equation, Green’s functions at an arbitrary (inner) depth level inside an unknown elastic layered medium can be retrieved from single-sided reflection data, which are collected at the top of the medium. To date, it has only been possible to obtain an exact solution if the medium obeyed stringent monotonicity conditions and if all forward-scattered (non-converted and converted) transmissions between the acquisition level and the inner depth level were known a priori. We introduce an alternative Marchenko equation by revising the window operators that are applied in its derivation. We also introduce an auxiliary equation for transmission data, which are collected at the bottom of the medium, and a coupled equation, which is based on both reflection and transmission data. We show that the joint system of the Marchenko equation, the auxiliary equation and the coupled equation can be succesfully inverted when broadband reflection and transmission data are available. This results in a novel methodology for elastodynamic Green’s function retrieval from two-sided data. Apart from these data, our approach requires P- and S-wave transmission times between the inner depth level and the top of the medium, as well as two angle-dependent amplitude scaling factors, which can be estimated from the data by enforcing energy conservation.
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20
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Massively parallel functional photoacoustic computed tomography of the human brain. Nat Biomed Eng 2022; 6:584-592. [PMID: 34059809 PMCID: PMC8630100 DOI: 10.1038/s41551-021-00735-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 04/21/2021] [Indexed: 12/13/2022]
Abstract
Blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging of the human brain requires bulky equipment for the generation of magnetic fields. Photoacoustic computed tomography obviates the need for magnetic fields by using light and sound to measure deoxyhaemoglobin and oxyhaemoglobin concentrations to then quantify oxygen saturation and blood volumes. Yet, the available imaging speeds, fields of view (FOV), sensitivities and penetration depths have been insufficient for functional imaging of the human brain. Here, we show that massively parallel ultrasonic transducers arranged hemispherically around the human head can produce tomographic images of the brain with a 10-cm-diameter FOV and spatial and temporal resolutions of 350 µm and 2 s, respectively. In patients who had a hemicraniectomy, a comparison of functional photoacoustic computed tomography and 7 T BOLD functional magnetic resonance imaging showed a strong spatial correspondence in the same FOV and a high temporal correlation between BOLD signals and photoacoustic signals, with the latter enabling faster detection of functional activation. Our findings establish the use of photoacoustic computed tomography for human brain imaging.
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21
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Lin L, Wang LV. The emerging role of photoacoustic imaging in clinical oncology. Nat Rev Clin Oncol 2022; 19:365-384. [PMID: 35322236 DOI: 10.1038/s41571-022-00615-3] [Citation(s) in RCA: 101] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2022] [Indexed: 12/13/2022]
Abstract
Clinical oncology can benefit substantially from imaging technologies that reveal physiological characteristics with multiscale observations. Complementing conventional imaging modalities, photoacoustic imaging (PAI) offers rapid imaging (for example, cross-sectional imaging in real time or whole-breast scanning in 10-15 s), scalably high levels of spatial resolution, safe operation and adaptable configurations. Most importantly, this novel imaging modality provides informative optical contrast that reveals details on anatomical, functional, molecular and histological features. In this Review, we describe the current state of development of PAI and the emerging roles of this technology in cancer screening, diagnosis and therapy. We comment on the performance of cutting-edge photoacoustic platforms, and discuss their clinical applications and utility in various clinical studies. Notably, the clinical translation of PAI is accelerating in the areas of macroscopic and mesoscopic imaging for patients with breast or skin cancers, as well as in microscopic imaging for histopathology. We also highlight the potential of future developments in technological capabilities and their clinical implications, which we anticipate will lead to PAI becoming a desirable and widely used imaging modality in oncological research and practice.
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Affiliation(s)
- Li Lin
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Lihong V Wang
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, California Institute of Technology, Pasadena, CA, USA. .,Department of Electrical Engineering, California Institute of Technology, Pasadena, CA, USA.
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22
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Cho SW, Park SM, Park B, Kim DY, Lee TG, Kim BM, Kim C, Kim J, Lee SW, Kim CS. High-speed photoacoustic microscopy: A review dedicated on light sources. PHOTOACOUSTICS 2021; 24:100291. [PMID: 34485074 PMCID: PMC8403586 DOI: 10.1016/j.pacs.2021.100291] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/18/2021] [Accepted: 08/03/2021] [Indexed: 05/05/2023]
Abstract
In recent years, many methods have been investigated to improve imaging speed in photoacoustic microscopy (PAM). These methods mainly focused upon three critical factors contributing to fast PAM: laser pulse repetition rate, scanning speed, and computing power of the microprocessors. A high laser repetition rate is fundamentally the most crucial factor to increase the PAM speed. In this paper, we review methods adopted for fast PAM systems in detail, specifically with respect to light sources. To the best of our knowledge, ours is the first review article analyzing the fundamental requirements for developing high-speed PAM and their limitations from the perspective of light sources.
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Affiliation(s)
- Soon-Woo Cho
- Department of Cogno-Mechatronics Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Sang Min Park
- Department of Cogno-Mechatronics Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Byullee Park
- Department of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Do Yeon Kim
- Safety Measurement Institute, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
- Department of Bio-Convergence Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Tae Geol Lee
- Safety Measurement Institute, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Beop-Min Kim
- Department of Bio-Convergence Engineering, Korea University, Seoul, 02841, Republic of Korea
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, 02481, Republic of Korea
| | - Chulhong Kim
- Department of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Jeesu Kim
- Department of Cogno-Mechatronics Engineering, Pusan National University, Busan, 46241, Republic of Korea
| | - Sang-Won Lee
- Safety Measurement Institute, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
- Department of Medical Physics, University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Chang-Seok Kim
- Department of Cogno-Mechatronics Engineering, Pusan National University, Busan, 46241, Republic of Korea
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23
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Luo X, Cai Y, Chen Z, Shan H, Sun X, Lin Q, Ma J, Wang B. Stack-Layer Dual-Element Ultrasonic Transducer for Broadband Functional Photoacoustic Tomography. Front Bioeng Biotechnol 2021; 9:786376. [PMID: 34778242 PMCID: PMC8581210 DOI: 10.3389/fbioe.2021.786376] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/18/2021] [Indexed: 11/13/2022] Open
Abstract
Current Photoacoustic tomography (PAT) approaches are based on a single-element transducer that exhibits compromised performance in clinical imaging applications. For example, vascular, tumors are likely to have complicated shapes and optical absorptions, covering relatively wide spectra in acoustic signals. The wide ultrasonic spectra make it difficult to set the detection bandwidth optimally in advance. In this work, we propose a stack-layer dual-element ultrasonic transducer for PAT. The central frequencies of the two piezoelectric elements are 3.06 MHz (99.3% bandwidth at -6 dB) and 11.07 MHz (85.2% bandwidth at -6 dB), respectively. This transducer bridges the sensitivity capability of ultrasound and the high contrast of optical methods in functional photoacoustic tomography. The dual-element transducer enabled multiscale analysis of the vascular network in rat brains. Using a multi-wavelength imaging scheme, the blood oxygen saturation was also detected. The preliminary results showed the great potential of broad-bandwidth functional PAT on vascular network visualization. The method can also be extended to whole-body imaging of small animals, breast cancer detection, and finger joint imaging.
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Affiliation(s)
- Xiaofei Luo
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, China
| | - Yiqi Cai
- School of Instrumentation and Optoelectronics Engineering, Beihang University, Beijing, China
| | - Zeyu Chen
- School of Mechanical and Electrical Engineering, Central South University, Changsha, China
| | - Han Shan
- School of Mechanical and Electrical Engineering, Central South University, Changsha, China
| | - Xin Sun
- School of Mechanical and Electrical Engineering, Central South University, Changsha, China
| | - Qibo Lin
- School of Mechanical and Electrical Engineering, Central South University, Changsha, China
| | - Jianguo Ma
- School of Instrumentation and Optoelectronics Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University, Beijing, China
| | - Bo Wang
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha, China
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24
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Park B, Han M, Park J, Kim T, Ryu H, Seo Y, Kim WJ, Kim HH, Kim C. A photoacoustic finder fully integrated with a solid-state dye laser and transparent ultrasound transducer. PHOTOACOUSTICS 2021; 23:100290. [PMID: 34401325 PMCID: PMC8358697 DOI: 10.1016/j.pacs.2021.100290] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/11/2021] [Accepted: 08/02/2021] [Indexed: 05/11/2023]
Abstract
The standard-of-care for evaluating lymph node status in breast cancers and melanoma metastasis is sentinel lymph node (SLN) assessment performed with a handheld gamma probe and radioisotopes. However, this method inevitably exposes patients and physicians to radiation, and the special facilities required limit its accessibility. Here, we demonstrate a non-ionizing, cost-effective, handheld photoacoustic finder (PAF) fully integrated with a solid-state dye laser and transparent ultrasound transducer (TUT). The solid-state dye laser handpiece is coaxially aligned with the spherically focused TUT. The integrated finder readily detected photoacoustic signals from a tube filled with methylene blue (MB) beneath a 22 mm thick layer of chicken tissue. In live animals, we also photoacoustically detected both SLNs injected with MB and subcutaneously injected melanomas. We believe that our radiation-free and inexpensive PAF can play a vital role in SLN assessment.
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Affiliation(s)
- Byullee Park
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and School of Interdisciplinary Bioscience and Bioengineering, Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, Republic of Korea
| | - Moongyu Han
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and School of Interdisciplinary Bioscience and Bioengineering, Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, Republic of Korea
| | - Jeongwoo Park
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and School of Interdisciplinary Bioscience and Bioengineering, Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, Republic of Korea
| | - Taejeong Kim
- Department of Chemistry, Postech-Catholic Biomedical Engineering Institute, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, 37673, Republic of Korea
| | - Hanyoung Ryu
- R&D center, Wontech Co. Ltd., Daejeon, 34028, Republic of Korea
| | - Youngseok Seo
- R&D center, Wontech Co. Ltd., Daejeon, 34028, Republic of Korea
| | - Won Jong Kim
- Department of Chemistry, Postech-Catholic Biomedical Engineering Institute, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, 37673, Republic of Korea
| | - Hyung Ham Kim
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and School of Interdisciplinary Bioscience and Bioengineering, Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, Republic of Korea
- Corresponding authors.
| | - Chulhong Kim
- Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, and School of Interdisciplinary Bioscience and Bioengineering, Medical Device Innovation Center, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, Republic of Korea
- Corresponding authors.
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25
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Yang X, Chen YH, Xia F, Sawan M. Photoacoustic imaging for monitoring of stroke diseases: A review. PHOTOACOUSTICS 2021; 23:100287. [PMID: 34401324 PMCID: PMC8353507 DOI: 10.1016/j.pacs.2021.100287] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 07/02/2021] [Accepted: 07/16/2021] [Indexed: 05/14/2023]
Abstract
Stroke is the leading cause of death and disability after ischemic heart disease. However, there is lacking a non-invasive long-time monitoring technique for stroke diagnosis and therapy. The photoacoustic imaging approach reconstructs images of an object based on the energy excitation by optical absorption and its conversion to acoustic waves, due to corresponding thermoelastic expansion, which has optical resolution and acoustic propagation. This emerging functional imaging method is a non-invasive technique. Due to its precision, this method is particularly attractive for stroke monitoring purpose. In this paper, we review the achievements of this technology and its applications on stroke, as well as the development status in both animal and human applications. Also, various photoacoustic systems and multi-modality photoacoustic imaging are introduced as for potential clinical applications. Finally, the challenges of photoacoustic imaging for monitoring stroke are discussed.
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Affiliation(s)
- Xi Yang
- Zhejiang University, Hangzhou, 310024, Zhejiang, China
- CenBRAIN Lab., School of Engineering, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
| | - Yun-Hsuan Chen
- CenBRAIN Lab., School of Engineering, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
| | - Fen Xia
- Zhejiang University, Hangzhou, 310024, Zhejiang, China
- CenBRAIN Lab., School of Engineering, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
| | - Mohamad Sawan
- CenBRAIN Lab., School of Engineering, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
- Corresponding author at: CenBRAIN Lab., School of Engineering, Westlake University, Hangzhou, 310024, Zhejiang, China.
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26
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Na S, Wang LV. Photoacoustic computed tomography for functional human brain imaging [Invited]. BIOMEDICAL OPTICS EXPRESS 2021; 12:4056-4083. [PMID: 34457399 PMCID: PMC8367226 DOI: 10.1364/boe.423707] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/05/2021] [Accepted: 06/08/2021] [Indexed: 05/02/2023]
Abstract
The successes of magnetic resonance imaging and modern optical imaging of human brain function have stimulated the development of complementary modalities that offer molecular specificity, fine spatiotemporal resolution, and sufficient penetration simultaneously. By virtue of its rich optical contrast, acoustic resolution, and imaging depth far beyond the optical transport mean free path (∼1 mm in biological tissues), photoacoustic computed tomography (PACT) offers a promising complementary modality. In this article, PACT for functional human brain imaging is reviewed in its hardware, reconstruction algorithms, in vivo demonstration, and potential roadmap.
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Affiliation(s)
- Shuai Na
- Caltech Optical Imaging Laboratory, Andrew
and Peggy Cherng Department of Medical Engineering,
California Institute of Technology, 1200
East California Boulevard, Pasadena, CA 91125, USA
| | - Lihong V. Wang
- Caltech Optical Imaging Laboratory, Andrew
and Peggy Cherng Department of Medical Engineering,
California Institute of Technology, 1200
East California Boulevard, Pasadena, CA 91125, USA
- Caltech Optical Imaging Laboratory,
Department of Electrical Engineering, California
Institute of Technology, 1200 East California Boulevard,
Pasadena, CA 91125, USA
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27
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Liang B, Wang S, Shen F, Liu QH, Gong Y, Yao J. Acoustic impact of the human skull on transcranial photoacoustic imaging. BIOMEDICAL OPTICS EXPRESS 2021; 12:1512-1528. [PMID: 33796369 PMCID: PMC7984784 DOI: 10.1364/boe.420084] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/10/2021] [Accepted: 02/12/2021] [Indexed: 05/03/2023]
Abstract
With balanced spatial resolution, imaging depth, and functional sensitivity, photoacoustic tomography (PAT) hold great promise for human brain imaging. However, the strong acoustic attenuation and aberration of the human skull (∼8 mm thick) are longstanding technical challenges for PAT of the human brain. In this work, we numerically investigated the impacts of the stratified human skull on photoacoustic wave propagation (i.e., the forward model) and PAT image formation (i.e., the inverse model). We simulated two representative transcranial PAT implementations: photoacoustic computed tomography (PACT) and photoacoustic macroscopy (PAMac). In the forward model, we simulated the detailed photoacoustic wave propagation from a point or line source through a digital human skull. The wave attenuation, refraction, mode conversation, and reverberation were thoroughly investigated. In the inverse model, we reconstructed the transcranial PACT and PAMac images of a point or line target enclosed by the human skull. Our results demonstrate that transcranial PAMac suffers mainly from wave reverberation within the skull, leading to prolonged signal duration and reduced axial resolution. Transcranial PACT is more susceptible to the skull's acoustic distortion, mode conversion, and reverberation, which collectively lead to strong image artifacts and deteriorated spatial resolutions. We also found that PACT with a ring-shaped transducer array shows more tolerance of the skull's adverse impacts and can provide more accurate image reconstruction. Our results suggest that incorporating the skull's geometry and acoustic properties can improve transcranial PAT image reconstruction. We expect that our results have provided a more comprehensive understanding of the acoustic impact of the human skull on transcranial PAT.
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Affiliation(s)
- Bingyang Liang
- School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, China
- National Key Laboratory on Vacuum Electronics, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, China
| | - Shaomeng Wang
- National Key Laboratory on Vacuum Electronics, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, China
| | - Fei Shen
- School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, China
| | - Qing Huo Liu
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, USA
| | - Yubin Gong
- School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, China
- National Key Laboratory on Vacuum Electronics, University of Electronic Science and Technology of China (UESTC), Chengdu 610054, China
| | - Junjie Yao
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
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