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Chen Z, Gezginer I, Zhou Q, Tang L, Deán-Ben XL, Razansky D. Multimodal optoacoustic imaging: methods and contrast materials. Chem Soc Rev 2024; 53:6068-6099. [PMID: 38738633 PMCID: PMC11181994 DOI: 10.1039/d3cs00565h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Indexed: 05/14/2024]
Abstract
Optoacoustic (OA) imaging offers powerful capabilities for interrogating biological tissues with rich optical absorption contrast while maintaining high spatial resolution for deep tissue observations. The spectrally distinct absorption of visible and near-infrared photons by endogenous tissue chromophores facilitates extraction of diverse anatomic, functional, molecular, and metabolic information from living tissues across various scales, from organelles and cells to whole organs and organisms. The primarily blood-related contrast and limited penetration depth of OA imaging have fostered the development of multimodal approaches to fully exploit the unique advantages and complementarity of the method. We review the recent hybridization efforts, including multimodal combinations of OA with ultrasound, fluorescence, optical coherence tomography, Raman scattering microscopy and magnetic resonance imaging as well as ionizing methods, such as X-ray computed tomography, single-photon-emission computed tomography and positron emission tomography. Considering that most molecules absorb light across a broad range of the electromagnetic spectrum, the OA interrogations can be extended to a large number of exogenously administered small molecules, particulate agents, and genetically encoded labels. This unique property further makes contrast moieties used in other imaging modalities amenable for OA sensing.
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Affiliation(s)
- 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
| | - Irmak Gezginer
- 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
| | - Quanyu Zhou
- 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
| | - Lin Tang
- 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
| | - 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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2
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Yu Y, Feng T, Qiu H, Gu Y, Chen Q, Zuo C, Ma H. Simultaneous photoacoustic and ultrasound imaging: A review. ULTRASONICS 2024; 139:107277. [PMID: 38460216 DOI: 10.1016/j.ultras.2024.107277] [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: 09/10/2023] [Revised: 01/09/2024] [Accepted: 02/26/2024] [Indexed: 03/11/2024]
Abstract
Photoacoustic imaging (PAI) is an emerging biomedical imaging technique that combines the advantages of optical and ultrasound imaging, enabling the generation of images with both optical resolution and acoustic penetration depth. By leveraging similar signal acquisition and processing methods, the integration of photoacoustic and ultrasound imaging has introduced a novel hybrid imaging modality suitable for clinical applications. Photoacoustic-ultrasound imaging allows for non-invasive, high-resolution, and deep-penetrating imaging, providing a wealth of image information. In recent years, with the deepening research and the expanding biomedical application scenarios of photoacoustic-ultrasound bimodal systems, the immense potential of photoacoustic-ultrasound bimodal imaging in basic research and clinical applications has been demonstrated, with some research achievements already commercialized. In this review, we introduce the principles, technical advantages, and biomedical applications of photoacoustic-ultrasound bimodal imaging techniques, specifically focusing on tomographic, microscopic, and endoscopic imaging modalities. Furthermore, we discuss the future directions of photoacoustic-ultrasound bimodal imaging technology.
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Affiliation(s)
- Yinshi Yu
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China
| | - Ting Feng
- Academy for Engineering & Technology, Fudan University, Shanghai 200433,China.
| | - Haixia Qiu
- First Medical Center of PLA General Hospital, Beijing, China
| | - Ying Gu
- First Medical Center of PLA General Hospital, Beijing, China
| | - Qian Chen
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China
| | - Chao Zuo
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China.
| | - Haigang Ma
- Smart Computational Imaging Laboratory (SCILab), School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210094, China; Smart Computational Imaging Research Institute (SCIRI) of Nanjing University of Science and Technology, Nanjing, Jiangsu Province 210019, China; Jiangsu Key Laboratory of Spectral Imaging & Intelligent Sense, Nanjing, Jiangsu Province 210094, China.
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Nyayapathi N, Zheng E, Zhou Q, Doyley M, Xia J. Dual-modal Photoacoustic and Ultrasound Imaging: from preclinical to clinical applications. FRONTIERS IN PHOTONICS 2024; 5:1359784. [PMID: 39185248 PMCID: PMC11343488 DOI: 10.3389/fphot.2024.1359784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Photoacoustic imaging is a novel biomedical imaging modality that has emerged over the recent decades. Due to the conversion of optical energy into the acoustic wave, photoacoustic imaging offers high-resolution imaging in depth beyond the optical diffusion limit. Photoacoustic imaging is frequently used in conjunction with ultrasound as a hybrid modality. The combination enables the acquisition of both optical and acoustic contrasts of tissue, providing functional, structural, molecular, and vascular information within the same field of view. In this review, we first described the principles of various photoacoustic and ultrasound imaging techniques and then classified the dual-modal imaging systems based on their preclinical and clinical imaging applications. The advantages of dual-modal imaging were thoroughly analyzed. Finally, the review ends with a critical discussion of existing developments and a look toward the future.
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Affiliation(s)
- Nikhila Nyayapathi
- Electrical and Computer Engineering, University of Rochester, Rochester, New York, 14627
| | - Emily Zheng
- Department of Biomedical Engineering, University at Buffalo, Buffalo, New York, 14226
| | - Qifa Zhou
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90007
| | - Marvin Doyley
- Electrical and Computer Engineering, University of Rochester, Rochester, New York, 14627
| | - Jun Xia
- Department of Biomedical Engineering, University at Buffalo, Buffalo, New York, 14226
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Wang Y, Sun N, Milne I, Cao R, Liu Q, Li Z, Guan Y, Yan Z, Hu S. Effects of Acute and Endurance Exercise on Cerebrovascular Function and Oxygen Metabolism: A Photoacoustic Microscopy Study. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:1651-1660. [PMID: 37966924 PMCID: PMC10754349 DOI: 10.1109/tuffc.2023.3331697] [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] [Indexed: 11/17/2023]
Abstract
Regular exercise improves the cerebrovascular function and has shown considerable therapeutic effects on a wide variety of brain diseases. However, the influence of exercise on different aspects of the cerebrovascular function remains to be comprehensively examined. In this study, we combined awake-brain photoacoustic microscopy (PAM) and a motorized treadmill to assess the effects of both acute exercise stimulation and endurance exercise training on the cerebrovascular function and cerebral oxygen metabolism under both physiological and pathological conditions. Acute exercise stimulation in nondiabetic mice resulted in robust vasodilation, increased cerebral blood flow (CBF), reduced oxygen extraction fraction (OEF), and unchanged cerebral metabolic rate of oxygen (CMRO2)-demonstrating the utility of this experimental setting to evaluate the cerebrovascular reactivity. Also, endurance exercise training for six weeks in diabetic mice reversed the diabetes-induced increases in the resting-state CBF and CMRO2 and maintained a stable OEF and CMRO2 under the acute exercise stimulation-shedding new light on how exercise protects the brain from diabetes-induced small vessel disease. In summary, we established an experimental approach to assess the effects of both acute exercise stimulation and endurance exercise training on the cerebrovascular function and tissue oxygen metabolism at the microscopic level and applied it to study the therapeutic benefits of endurance exercise training in diabetic mice.
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John S, Hester S, Basij M, Paul A, Xavierselvan M, Mehrmohammadi M, Mallidi S. Niche preclinical and clinical applications of photoacoustic imaging with endogenous contrast. PHOTOACOUSTICS 2023; 32:100533. [PMID: 37636547 PMCID: PMC10448345 DOI: 10.1016/j.pacs.2023.100533] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/30/2023] [Accepted: 07/14/2023] [Indexed: 08/29/2023]
Abstract
In the past decade, photoacoustic (PA) imaging has attracted a great deal of popularity as an emergent diagnostic technology owing to its successful demonstration in both preclinical and clinical arenas by various academic and industrial research groups. Such steady growth of PA imaging can mainly be attributed to its salient features, including being non-ionizing, cost-effective, easily deployable, and having sufficient axial, lateral, and temporal resolutions for resolving various tissue characteristics and assessing the therapeutic efficacy. In addition, PA imaging can easily be integrated with the ultrasound imaging systems, the combination of which confers the ability to co-register and cross-reference various features in the structural, functional, and molecular imaging regimes. PA imaging relies on either an endogenous source of contrast (e.g., hemoglobin) or those of an exogenous nature such as nano-sized tunable optical absorbers or dyes that may boost imaging contrast beyond that provided by the endogenous sources. In this review, we discuss the applications of PA imaging with endogenous contrast as they pertain to clinically relevant niches, including tissue characterization, cancer diagnostics/therapies (termed as theranostics), cardiovascular applications, and surgical applications. We believe that PA imaging's role as a facile indicator of several disease-relevant states will continue to expand and evolve as it is adopted by an increasing number of research laboratories and clinics worldwide.
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Affiliation(s)
- Samuel John
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| | - Scott Hester
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Maryam Basij
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| | - Avijit Paul
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | | | - Mohammad Mehrmohammadi
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, USA
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
- Wilmot Cancer Institute, Rochester, NY, USA
| | - Srivalleesha Mallidi
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
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Stamenkovic S, Li Y, Waters J, Shih A. Deep Imaging to Dissect Microvascular Contributions to White Matter Degeneration in Rodent Models of Dementia. Stroke 2023; 54:1403-1415. [PMID: 37094035 PMCID: PMC10460612 DOI: 10.1161/strokeaha.122.037156] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
The increasing socio-economic burden of Alzheimer disease (AD) and AD-related dementias has created a pressing need to define targets for therapeutic intervention. Deficits in cerebral blood flow and neurovascular function have emerged as early contributors to disease progression. However, the cause, progression, and consequence of small vessel disease in AD/AD-related dementias remains poorly understood, making therapeutic targets difficult to pinpoint. Animal models that recapitulate features of AD/AD-related dementias may provide mechanistic insight because microvascular pathology can be studied as it develops in vivo. Recent advances in in vivo optical and ultrasound-based imaging of the rodent brain facilitate this goal by providing access to deeper brain structures, including white matter and hippocampus, which are more vulnerable to injury during cerebrovascular disease. Here, we highlight these novel imaging approaches and discuss their potential for improving our understanding of vascular contributions to AD/AD-related dementias.
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Affiliation(s)
- Stefan Stamenkovic
- Center for Developmental Biology and Regenerative Medicine, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Yuandong Li
- Center for Developmental Biology and Regenerative Medicine, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Jack Waters
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Andy Shih
- Center for Developmental Biology and Regenerative Medicine, Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
- Allen Institute for Brain Science, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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7
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Huang J, Chen L, Yao ZM, Sun XR, Tong XH, Dong SY. The role of mitochondrial dynamics in cerebral ischemia-reperfusion injury. Biomed Pharmacother 2023; 162:114671. [PMID: 37037094 DOI: 10.1016/j.biopha.2023.114671] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/12/2023] Open
Abstract
Stroke is one of the leading causes of death and long-term disability worldwide. More than 80 % of strokes are ischemic, caused by an occlusion of cerebral arteries. Without question, restoration of blood supply as soon as possible is the first therapeutic strategy. Nonetheless paradoxically, reperfusion can further aggravate the injury through a series of reactions known as cerebral ischemia-reperfusion injury (CIRI). Mitochondria play a vital role in promoting nerve survival and neurological function recovery and mitochondrial dysfunction is considered one of the characteristics of CIRI. Neurons often die due to oxidative stress and an imbalance in energy metabolism following CIRI, and there is a strong association with mitochondrial dysfunction. Altered mitochondrial dynamics is the first reaction of mitochondrial stress. Mitochondrial dynamics refers to the maintenance of the integrity, distribution, and size of mitochondria as well as their ability to resist external stimuli through a continuous cycle of mitochondrial fission and fusion. Therefore, improving mitochondrial dynamics is a vital means of treating CIRI. This review discusses the relationship between mitochondria and CIRI and emphasizes improving mitochondrial dynamics as a potential therapeutic approach to improve the prognosis of CIRI.
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Affiliation(s)
- Jie Huang
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China
| | - Lei Chen
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China
| | - Zi-Meng Yao
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China
| | - Xiao-Rong Sun
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China
| | - Xu-Hui Tong
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China
| | - Shu-Ying Dong
- Department of Pharmacology, School of Pharmacy, Bengbu Medical College, Bengbu, China; Anhui Engineering Technology Research Center of Biochemical Pharmaceutical, Bengbu, China; Bengbu Medical College Key Laboratory of Cardiovascular and Cerebrovascular Diseases, Bengbu, China.
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8
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Zhu J, Chen J, Amjadian M, Liang S, Qu Z, Wang Y, Zhang Y, Wang L. Simultaneous dual-modal photoacoustic and harmonic ultrasound microscopy with an optimized acoustic combiner. BIOMEDICAL OPTICS EXPRESS 2023; 14:1626-1635. [PMID: 37078044 PMCID: PMC10110316 DOI: 10.1364/boe.484038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 05/03/2023]
Abstract
Simultaneous photoacoustic (PA) and ultrasound (US) imaging provides rich optical and acoustic contrasts with high sensitivity, specificity, and resolution, making it a promising tool for diagnosing and assessing various diseases. However, the resolution and penetration depth tend to be contradictory due to the increased attenuation of high-frequency ultrasound. To address this issue, we present simultaneous dual-modal PA/US microscopy with an optimized acoustic combiner that can maintain high resolution while improving the penetration of ultrasound imaging. A low-frequency ultrasound transducer is used for acoustic transmission, and a high-frequency transducer is used for PA and US detection. An acoustic beam combiner is utilized to merge the transmitting and receiving acoustic beams with a predetermined ratio. By combining the two different transducers, harmonic US imaging and high-frequency photoacoustic microscopy are implemented. In vivo experiments on the mouse brain demonstrate the simultaneous PA and US imaging ability. The harmonic US imaging of the mouse eye reveals finer iris and lens boundary structures than conventional US imaging, providing a high-resolution anatomical reference for co-registered PA imaging.
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Affiliation(s)
- Jingyi Zhu
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Jiangbo Chen
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Mohammadreza Amjadian
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
- Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Siyi Liang
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Zheng Qu
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Yue Wang
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Yachao Zhang
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Lidai Wang
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
- City University of Hong Kong Shenzhen Research Institute, Yuexing Yi Dao, Nanshan District, China
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Zhou Y, Sun N, Hu S. Deep Learning-Powered Bessel-Beam Multiparametric Photoacoustic Microscopy. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:3544-3551. [PMID: 35788453 PMCID: PMC9767649 DOI: 10.1109/tmi.2022.3188739] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Enabling simultaneous and high-resolution quantification of the total concentration of hemoglobin ( [Formula: see text]), oxygen saturation of hemoglobin (sO2), and cerebral blood flow (CBF), multi-parametric photoacoustic microscopy (PAM) has emerged as a promising tool for functional and metabolic imaging of the live mouse brain. However, due to the limited depth of focus imposed by the Gaussian-beam excitation, the quantitative measurements become inaccurate when the imaging object is out of focus. To address this problem, we have developed a hardware-software combined approach by integrating Bessel-beam excitation and conditional generative adversarial network (cGAN)-based deep learning. Side-by-side comparison of the new cGAN-powered Bessel-beam multi-parametric PAM against the conventional Gaussian-beam multi-parametric PAM shows that the new system enables high-resolution, quantitative imaging of [Formula: see text], sO2, and CBF over a depth range of [Formula: see text] in the live mouse brain, with errors 13-58 times lower than those of the conventional system. Better fulfilling the rigid requirement of light focusing for accurate hemodynamic measurements, the deep learning-powered Bessel-beam multi-parametric PAM may find applications in large-field functional recording across the uneven brain surface and beyond (e.g., tumor imaging).
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Ahn J, Baik JW, Kim Y, Choi K, Park J, Kim H, Kim JY, Kim HH, Nam SH, Kim C. Fully integrated photoacoustic microscopy and photoplethysmography of human in vivo. PHOTOACOUSTICS 2022; 27:100374. [PMID: 35646590 PMCID: PMC9133750 DOI: 10.1016/j.pacs.2022.100374] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/08/2022] [Accepted: 05/17/2022] [Indexed: 05/05/2023]
Abstract
Photoacoustic microscopy (PAM) is used to visualize blood vessels and to monitor their time-dependent changes. Photoplethysmography (PPG) measures hemodynamic time-series changes such as heart rate. However, PPG's limited visual access to the dynamic changes of blood vessels has prohibited further understanding of hemodynamics. Here, we propose a novel, fully integrated PAM and photoplethysmography (PAM-PPG) system to understand hemodynamic features in detail. Using the PAM-PPG system, we simultaneously acquire vascular images (by PAM) and changes in the blood volume (by PPG) from human fingers. Next, we determine the heart rate from changes in the PA signals, which match well with the PPG signals. These changes can be measured if the blood flow is not blocked. From the results, we believe that PAM-PPG could be a useful clinical tool in various clinical fields such as cardiology and endocrinology.
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Affiliation(s)
- Joongho Ahn
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Jin Woo Baik
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Yeonggeon Kim
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Karam Choi
- Samsung Advanced Institute of Technology, Samsung Electronics Co. Ltd., Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - Jeongwoo Park
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Hyojin Kim
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Jin Young Kim
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Hyung Ham Kim
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
| | - Sung Hyun Nam
- Samsung Advanced Institute of Technology, Samsung Electronics Co. Ltd., Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - Chulhong Kim
- Departments of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, and Medical Device Innovation Center, Pohang University of Science and Technology, Pohang-si, Gyeongsangbuk-do 37673, Republic of Korea
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Li W, Liu YH, Estrada H, Rebling J, Reiss M, Galli S, Nombela-Arrieta C, Razansky D. Tracking Strain-Specific Morphogenesis and Angiogenesis of Murine Calvaria with Large-Scale Optoacoustic and Ultrasound Microscopy. J Bone Miner Res 2022; 37:1032-1043. [PMID: 35220594 PMCID: PMC9311448 DOI: 10.1002/jbmr.4533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 01/30/2022] [Accepted: 02/20/2022] [Indexed: 11/25/2022]
Abstract
Skull bone development is a dynamic and well-coordinated process playing a key role in maturation and maintenance of the bone marrow (BM), fracture healing, and progression of diseases such as osteoarthritis or osteoporosis. At present, dynamic transformation of the growing bone (osteogenesis) as well as its vascularization (angiogenesis) remain largely unexplored due to the lack of suitable in vivo imaging techniques capable of noninvasive visualization of the whole developing calvaria at capillary-level resolution. We present a longitudinal study on skull bone development using ultrasound-aided large-scale optoacoustic microscopy (U-LSOM). Skull bone morphogenesis and microvascular growth patterns were monitored in three common mouse strains (C57BL/6J, CD-1, and Athymic Nude-Foxn1nu) at the whole-calvaria scale over a 3-month period. Strain-specific differences in skull development were revealed by quantitative analysis of bone and vessel parameters, indicating the coupling between angiogenesis and osteogenesis during skull bone growth in a minimally invasive and label-free manner. The method further enabled identifying BM-specific sinusoidal vessels, and superficial skull vessels penetrating into BM compartments. Our approach furnishes a new high-throughput longitudinal in vivo imaging platform to study morphological and vascular skull alterations in health and disease, shedding light on the critical links between blood vessel formation, skull growth, and regeneration. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Weiye Li
- Institute for Biomedical Engineering and 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
| | - Yu-Hang Liu
- Institute for Biomedical Engineering and 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
| | - Héctor Estrada
- Institute for Biomedical Engineering and 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
| | - Johannes Rebling
- Institute for Biomedical Engineering and 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
| | - Michael Reiss
- Institute for Biomedical Engineering and 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
| | - Serena Galli
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - César Nombela-Arrieta
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - Daniel Razansky
- Institute for Biomedical Engineering and 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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Sun N, Bruce AC, Ning B, Cao R, Wang Y, Zhong F, Peirce SM, Hu S. Photoacoustic microscopy of vascular adaptation and tissue oxygen metabolism during cutaneous wound healing. BIOMEDICAL OPTICS EXPRESS 2022; 13:2695-2706. [PMID: 35774317 PMCID: PMC9203110 DOI: 10.1364/boe.456198] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 06/15/2023]
Abstract
Cutaneous wounds affect millions of people every year. Vascularization and blood oxygen delivery are critical bottlenecks in wound healing, and understanding the spatiotemporal dynamics of these processes may lead to more effective therapeutic strategies to accelerate wound healing. In this work, we applied multi-parametric photoacoustic microscopy (PAM) to study vascular adaptation and the associated changes in blood oxygen delivery and tissue oxygen metabolism throughout the hemostasis, inflammatory, proliferation, and early remodeling phases of wound healing in mice with skin puncture wounds. Multifaceted changes in the vascular structure, function, and tissue oxygen metabolism were observed during the 14-day monitoring of wound healing. On the entire wound area, significant elevations of the arterial blood flow and tissue oxygen metabolism were observed right after wounding and remained well above the baseline over the 14-day period. On the healing front, biphasic changes in the vascular density and blood flow were observed, both of which peaked on day 1, remained elevated in the first week, and returned to the baselines by day 14. Along with the wound closure and thickening, tissue oxygen metabolism in the healing front remained elevated even after structural and functional changes in the vasculature were stabilized. On the newly formed tissue, significantly higher blood oxygenation, flow, and tissue metabolism were observed compared to those before wounding. Blood oxygenation and flow in the new tissue appeared to be independent of when it was formed, but instead showed noticeable dependence on the phase of wound healing. This PAM study provides new insights into the structural, functional, and metabolic changes associated with vascular adaptation during wound healing and suggests that the timing and target of vascular treatments for wound healing may affect the outcomes.
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Affiliation(s)
- Naidi Sun
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Anthony C. Bruce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Bo Ning
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Yiming Wang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Fenghe Zhong
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Shayn M. Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
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Norambuena A, Sun X, Wallrabe H, Cao R, Sun N, Pardo E, Shivange N, Wang DB, Post LA, Ferris HA, Hu S, Periasamy A, Bloom GS. SOD1 mediates lysosome-to-mitochondria communication and its dysregulation by amyloid-β oligomers. Neurobiol Dis 2022; 169:105737. [PMID: 35452786 PMCID: PMC9291271 DOI: 10.1016/j.nbd.2022.105737] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/24/2022] [Accepted: 04/15/2022] [Indexed: 11/29/2022] Open
Abstract
Altered mitochondrial DNA (mtDNA) occurs in neurodegenerative disorders like Alzheimer's disease (AD); how mtDNA synthesis is linked to neurodegeneration is poorly understood. We previously discovered Nutrient-induced Mitochondrial Activity (NiMA), an inter-organelle signaling pathway where nutrient-stimulated lysosomal mTORC1 activity regulates mtDNA replication in neurons by a mechanism sensitive to amyloid-β oligomers (AβOs), a primary factor in AD pathogenesis (Norambuena et al., 2018). Using 5-ethynyl-2'-deoxyuridine (EdU) incorporation into mtDNA of cultured neurons, along with photoacoustic and mitochondrial metabolic imaging of cultured neurons and mouse brains, we show these effects being mediated by mTORC1-catalyzed T40 phosphorylation of superoxide dismutase 1 (SOD1). Mechanistically, tau, another key factor in AD pathogenesis and other tauopathies, reduced the lysosomal content of the tuberous sclerosis complex (TSC), thereby increasing NiMA and suppressing SOD1 activity and mtDNA synthesis. AβOs inhibited these actions. Dysregulation of mtDNA synthesis was observed in fibroblasts derived from tuberous sclerosis (TS) patients, who lack functional TSC and elevated SOD1 activity was also observed in human AD brain. Together, these findings imply that tau and SOD1 couple nutrient availability to mtDNA replication, linking mitochondrial dysfunction to AD.
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Affiliation(s)
- Andrés Norambuena
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.
| | - Xuehan Sun
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
| | - Horst Wallrabe
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
| | - Ruofan Cao
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA; W.M. Keck Center for Cellular Imaging, University of Virginia, Charlottesville, VA 22904, USA
| | - Naidi Sun
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Evelyn Pardo
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
| | - Nutan Shivange
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
| | - Dora Bigler Wang
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
| | - Lisa A Post
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22904, USA; Division of Endocrinology & Metabolism, School of Medicine, University of Virginia, Charlottesville, VA 22904, USA
| | - Heather A Ferris
- Department of Neuroscience, University of Virginia, Charlottesville, VA 22904, USA; Division of Endocrinology & Metabolism, School of Medicine, University of Virginia, Charlottesville, VA 22904, USA
| | - Song Hu
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Ammasi Periasamy
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA; W.M. Keck Center for Cellular Imaging, University of Virginia, Charlottesville, VA 22904, USA
| | - George S Bloom
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA; Department of Cell Biology, University of Virginia, Charlottesville, VA 22904, USA; Department of Neuroscience, University of Virginia, Charlottesville, VA 22904, USA
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Wang Z, Zhou Y, Hu S. Sparse Coding-Enabled Low-Fluence Multi-Parametric Photoacoustic Microscopy. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:805-814. [PMID: 34710042 PMCID: PMC9036083 DOI: 10.1109/tmi.2021.3124124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Uniquely capable of simultaneous imaging of the hemoglobin concentration, blood oxygenation, and flow speed at the microvascular level in vivo, multi-parametric photoacoustic microscopy (PAM) has shown considerable impact in biomedicine. However, the multi-parametric PAM acquisition requires dense sampling and thus a high laser pulse repetition rate (up to MHz), which sets a strict limit on the applicable pulse energy due to safety considerations. A similar limitation is shared by high-speed PAM, which also uses lasers with high pulse repetition rates. To achieve high quantitative accuracy besides good structural visualization at low levels of laser fluence in PAM, we have developed a new, sparse coding-based two-step denoising technique. In the setting of intravital brain imaging, we demonstrated that this unsupervised learning approach enabled the reduction of the laser fluence in PAM by 5 times without compromise of the image quality (structural similarity index measure or SSIM: >0.92) and the quantitative accuracy (errors: <4.9%). Offering a significant relaxation in the requirement of PAM on laser fluence while maintaining the quality of structural imaging and accuracy of quantitative measurements, this sparse coding-based approach is expected to facilitate the application and clinical translation of multi-parametric PAM and high-speed PAM, which have a tight photon budget due to either safety considerations or laser source limitations.
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Choi W, Park EY, Jeon S, Yang Y, Park B, Ahn J, Cho S, Lee C, Seo DK, Cho JH, Kim C. Three-dimensional Multistructural Quantitative Photoacoustic and US Imaging of Human Feet in Vivo. Radiology 2022; 303:467-473. [PMID: 35191741 DOI: 10.1148/radiol.211029] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Background Monitoring the microcirculation in human feet is crucial in assessing peripheral vascular diseases, such as diabetic foot. However, conventional imaging modalities are more focused on diagnosis in major arteries, and there are limited methods to provide microvascular information in early stages of the disease. Purpose To investigate a three-dimensional (3D) noncontrast bimodal photoacoustic (PA)/US imaging system that visualizes the human foot morphologically and also reliably quantifies podiatric vascular parameters noninvasively. Materials and Methods A clinically relevant PA/US imaging system was combined with a foot scanner to obtain 3D PA and US images of the human foot in vivo. Healthy participants were recruited from September 2020 to June 2021. The collected 3D PA and US images were postprocessed to present structural information about the foot. The quantitative reliability was evaluated in five repeated scans of 10 healthy feet by calculating the intraclass correlation coefficient and minimal detectable change, and the detectability of microvascular changes was tested by imaging 10 healthy feet intentionally occluded with use of a pressure cuff (160 mm Hg). Statistically significant difference is indicated with P values. Results Ten feet from six healthy male volunteers (mean age ± standard deviation, 27 years ± 3) were included. The foot images clearly visualized the structure of the vasculature, bones, and skin and provided such functional information as the total hemoglobin concentration (HbT), hemoglobin oxygen saturation (SO2), vessel density, and vessel depth. Functional information from five independent measurements of 10 healthy feet was moderately reliable (intraclass correlation coefficient, 0.51-0.74). Significant improvements in HbT (P = .006) and vessel density (P = .046) as well as the retention of SO2 were observed, which accurately described the microvascular change due to venous occlusion. Conclusion Three-dimensional photoacoustic and US imaging was able to visualize morphologic and physiologic features of the human foot, including the peripheral microvasculature, in healthy volunteers. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Mezrich in this issue.
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Affiliation(s)
- Wonseok Choi
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Eun-Yeong Park
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Seungwan Jeon
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Yeoree Yang
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Byullee Park
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Joongho Ahn
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Seonghee Cho
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Changyeop Lee
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Dong-Kyo Seo
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Jae-Hyoung Cho
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
| | - Chulhong Kim
- From the Departments of Convergence IT Engineering (W.C., E.Y.P, S.J., B.P., J.A., C.K.), Electrical Engineering (C.K.), Mechanical Engineering (C.L., C.K.), School of Interdisciplinary Bioscience and Bioengineering (S.C.), and Medical Device Innovation Center (W.C., E.Y.P., S.J., B.P., J.A., S.C., C.L., C.K.), Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang 37673, Korea; Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Catholic Smart Health Care Center, The Catholic University of Korea, Seoul, Korea (Y.Y., J.H.C.); Gangneung Asan Hospital, University of Ulsan College of Medicine, Seoul, Korea (D.K.S.); and Opticho, Pohang, Korea (C.K.)
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Sathyanarayana SG, Wang Z, Sun N, Ning B, Hu S, Hossack JA. Recovery of Blood Flow From Undersampled Photoacoustic Microscopy Data Using Sparse Modeling. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:103-120. [PMID: 34388091 DOI: 10.1109/tmi.2021.3104521] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Photoacoustic microscopy (PAM) leverages the optical absorption contrast of blood hemoglobin for high-resolution, multi-parametric imaging of the microvasculature in vivo. However, to quantify the blood flow speed, dense spatial sampling is required to assess blood flow-induced loss of correlation of sequentially acquired A-line signals, resulting in increased laser pulse repetition rate and consequently optical fluence. To address this issue, we have developed a sparse modeling approach for blood flow quantification based on downsampled PAM data. Evaluation of its performance both in vitro and in vivo shows that this sparse modeling method can accurately recover the substantially downsampled data (up to 8 times) for correlation-based blood flow analysis, with a relative error of 12.7 ± 6.1 % across 10 datasets in vitro and 12.7 ± 12.1 % in vivo for data downsampled 8 times. Reconstruction with the proposed method is on par with recovery using compressive sensing, which exhibits an error of 12.0 ± 7.9 % in vitro and 33.86 ± 26.18 % in vivo for data downsampled 8 times. Both methods outperform bicubic interpolation, which shows an error of 15.95 ± 9.85 % in vitro and 110.7 ± 87.1 % in vivo for data downsampled 8 times.
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Mahmoodkalayeh S, Kratkiewicz K, Manwar R, Shahbazi M, Ansari MA, Natarajan G, Asano E, Avanaki K. Wavelength and pulse energy optimization for detecting hypoxia in photoacoustic imaging of the neonatal brain: a simulation study. BIOMEDICAL OPTICS EXPRESS 2021; 12:7458-7477. [PMID: 35003846 PMCID: PMC8713673 DOI: 10.1364/boe.439147] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/10/2021] [Accepted: 10/20/2021] [Indexed: 05/03/2023]
Abstract
Cerebral hypoxia is a severe injury caused by oxygen deprivation to the brain. Hypoxia in the neonatal period increases the risk for the development of neurological disorders, including hypoxic-ischemic encephalopathy, cerebral palsy, periventricular leukomalacia, and hydrocephalus. It is crucial to recognize hypoxia as soon as possible because early intervention improves outcomes. Photoacoustic imaging, using at least two wavelengths, through a spectroscopic analysis, can measure brain oxygen saturation. Due to the spectral coloring effect arising from the dependency of optical properties of biological tissues to the wavelength of light, choosing the right wavelength-pair for efficient and most accurate oxygen saturation measurement and consequently quantifying hypoxia at a specific depth is critical. Using a realistic neonate head model and Monte Carlo simulations, we found practical wavelength-pairs that quantified regions with hypoxia most accurately at different depths down to 22 mm into the cortex neighboring the lateral ventricle. We also demonstrated, for the first time, that the accuracy of the sO2 measurement can be increased by adjusting the level of light energy for each wavelength-pair. Considering the growing interest in photoacoustic imaging of the brain, this work will assist in a more accurate use of photoacoustic spectroscopy and help in the clinical translation of this promising imaging modality. Please note that explaining the effect of acoustic aberration of the skull is not in the scope of this study.
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Affiliation(s)
- Sadreddin Mahmoodkalayeh
- Department of Physics, Shahid Beheshti University, Tehran, Iran
- Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran
- These authors have contributed equally
| | - Karl Kratkiewicz
- Wayne State University, Bioengineering Department, Detroit, Michigan 48201, USA
| | - Rayyan Manwar
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, USA
| | - Meysam Shahbazi
- Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran
| | - Mohammad Ali Ansari
- Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran
| | - Girija Natarajan
- Wayne State University School of Medicine, Department of Neurology, Detroit, Michigan 48201, USA
- Wayne State University School of Medicine, Department of Pediatrics, Detroit, Michigan 48201, USA
| | - Eishi Asano
- Wayne State University School of Medicine, Department of Neurology, Detroit, Michigan 48201, USA
- Wayne State University School of Medicine, Department of Pediatrics, Detroit, Michigan 48201, USA
| | - Kamran Avanaki
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois 60607, USA
- Department of Dermatology, University of Illinois at Chicago, Chicago, Illinois 60607, USA
- These authors have contributed equally
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18
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Sciortino VM, Tran A, Sun N, Cao R, Sun T, Sun YY, Yan P, Zhong F, Zhou Y, Kuan CY, Lee JM, Hu S. Longitudinal cortex-wide monitoring of cerebral hemodynamics and oxygen metabolism in awake mice using multi-parametric photoacoustic microscopy. J Cereb Blood Flow Metab 2021; 41:3187-3199. [PMID: 34304622 PMCID: PMC8669277 DOI: 10.1177/0271678x211034096] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Multi-parametric photoacoustic microscopy (PAM) has emerged as a promising new technique for high-resolution quantification of hemodynamics and oxygen metabolism in the mouse brain. In this work, we have extended the scope of multi-parametric PAM to longitudinal, cortex-wide, awake-brain imaging with the use of a long-lifetime (24 weeks), wide-field (5 × 7 mm2), light-weight (2 g), dual-transparency (i.e., light and ultrasound) cranial window. Cerebrovascular responses to the window installation were examined in vivo, showing a complete recovery in 18 days. In the 22-week monitoring after the recovery, no dura thickening, skull regrowth, or changes in cerebrovascular structure and function were observed. The promise of this technique was demonstrated by monitoring vascular and metabolic responses of the awake mouse brain to ischemic stroke throughout the acute, subacute, and chronic stages. Side-by-side comparison of the responses in the ipsilateral (injury) and contralateral (control) cortices shows that despite an early recovery of cerebral blood flow and an increase in microvessel density, a long-lasting deficit in cerebral oxygen metabolism was observed throughout the chronic stage in the injured cortex, part of which proceeded to infarction. This longitudinal, functional-metabolic imaging technique opens new opportunities to study the chronic progression and therapeutic responses of neurovascular diseases.
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Affiliation(s)
- Vincent M Sciortino
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA
| | - Angela Tran
- Department of Biology, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA
| | - Naidi Sun
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Rui Cao
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA
| | - Tao Sun
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Yu-Yo Sun
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Ping Yan
- Department of Neuroscience, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA
| | - Fenghe Zhong
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Yifeng Zhou
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Chia-Yi Kuan
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Jin-Moo Lee
- Department of Neuroscience, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Song Hu
- Department of Biomedical Engineering, 2358University of Virginia, University of Virginia, Charlottesville, VA, USA.,Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
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19
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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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20
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Cao R, Tran A, Li J, Xu Z, Sun N, Zuo Z, Hu S. Hemodynamic and oxygen-metabolic responses of the awake mouse brain to hypercapnia revealed by multi-parametric photoacoustic microscopy. J Cereb Blood Flow Metab 2021; 41:2628-2639. [PMID: 33899557 PMCID: PMC8504963 DOI: 10.1177/0271678x211010352] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 03/13/2021] [Accepted: 03/18/2021] [Indexed: 11/16/2022]
Abstract
A widely used cerebrovascular stimulus and common pathophysiologic condition, hypercapnia is of great interest in brain research. However, it remains controversial how hypercapnia affects brain hemodynamics and energy metabolism. By using multi-parametric photoacoustic microscopy, the multifaceted responses of the awake mouse brain to different levels of hypercapnia are investigated. Our results show significant and vessel type-dependent increases of the vessel diameter and blood flow in response to the hypercapnic challenges, along with a decrease in oxygen extraction fraction due to elevated venous blood oxygenation. Interestingly, the increased blood flow and decreased oxygen extraction are not commensurate with each other, which leads to reduced cerebral oxygen metabolism. Further, time-lapse imaging over 2-hour chronic hypercapnic challenges reveals that the structural, functional, and metabolic changes induced by severe hypercapnia (10% CO2) are not only more pronounced but more enduring than those induced by mild hypercapnia (5% CO2), indicating that the extent of brain's compensatory response to chronic hypercapnia is inversely related to the severity of the challenge. Offering quantitative, dynamic, and CO2 level-dependent insights into the hemodynamic and metabolic responses of the brain to hypercapnia, these findings might provide useful guidance to the application of hypercapnia in brain research.
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Affiliation(s)
- Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Angela Tran
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Jun Li
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA
| | - Zhiqiang Xu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Naidi Sun
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA
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21
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Chen Q, Jin T, Qi W, Xi L. Dual-model wearable photoacoustic microscopy and electroencephalograph: study of neurovascular coupling in anesthetized and freely moving rats. BIOMEDICAL OPTICS EXPRESS 2021; 12:6614-6628. [PMID: 34745760 PMCID: PMC8547996 DOI: 10.1364/boe.438596] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/11/2021] [Accepted: 09/14/2021] [Indexed: 05/29/2023]
Abstract
Observing microscale neurovascular dynamics under different physiological conditions is of great importance to understanding brain functions and disorders. Here, we report a dual-model wearable device and an auxiliary data processing algorithm to derive neurovascular dynamics. The device integrates high-resolution photoacoustic microscopy and electroencephalography (EEG), which allows observing capillary-level hemodynamics and neural activities in anesthesia and freely moving rats. By using the developed algorithm, multiple photoacoustic/EEG parameters extracted and correlated enables investigation of the interplay between neural and vascular activities. We employed this platform to study the neurovascular coupling during different types of seizures in rats under various physiological conditions. We observed cerebral vascular vasodilation/constriction corresponding well to the seizure on/off in rats under regular anesthesia conditions, showing a strong neurovascular coupling coefficient. In rats under weak anesthesia and freely moving conditions, more intense cerebral hemodynamics and neural activities occurred with a weaker neurovascular coupling coefficient. The comprehensively quantitative analyses suggest that anesthesia has a dominant impact on the seizure onset and affect the neurovascular coupling correlation in the current drug-induced localized seizure model. Our study reveals that the designed platform has the potential to support studies on brain functions and disorders in diseased rodent models in various physiological states.
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Affiliation(s)
- Qian Chen
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Tian Jin
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Weizhi Qi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Lei Xi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
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22
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Zhou Y, Zhong F, Yan P, Lee JM, Hu S. Simultaneous imaging of amyloid deposition and cerebrovascular function using dual-contrast photoacoustic microscopy. OPTICS LETTERS 2021; 46:2561-2564. [PMID: 34061056 DOI: 10.1364/ol.419817] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/29/2021] [Indexed: 06/12/2023]
Abstract
Pathological aggregation of Aβ peptides results in the deposition of amyloid in the brain parenchyma (senile plaques in Alzheimer's disease [AD]) and around cerebral microvessels (cerebral amyloid angiopathy [CAA]). Our current understanding of the amyloid-induced microvascular changes has been limited to the structure and hemodynamics-leaving the oxygen-metabolic aspect unattended. In this Letter, we report a dual-contrast photoacoustic microscopy (PAM) technique, which integrates the molecular contrast of dichroism PAM and the physiological contrast of multi-parametric PAM for simultaneous, intravital imaging of amyloid deposition and cerebrovascular function in a mouse model that develops AD and CAA. This technique opens up new opportunities to study the spatiotemporal interplay between amyloid deposition and vascular-metabolic dysfunction in AD and CAA.
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23
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Zhou Y, Zhong F, Hu S. Temporal and spectral unmixing of photoacoustic signals by deep learning. OPTICS LETTERS 2021; 46:2690-2693. [PMID: 34061089 PMCID: PMC9385116 DOI: 10.1364/ol.426678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/09/2021] [Indexed: 05/18/2023]
Abstract
Improving the imaging speed of multi-parametric photoacoustic microscopy (PAM) is essential to leveraging its impact in biomedicine. However, to avoid temporal overlap, the A-line rate is limited by the acoustic speed in biological tissues to a few megahertz. Moreover, to achieve high-speed PAM of the oxygen saturation of hemoglobin, the stimulated Raman scattering effect in optical fibers has been widely used to generate 558 nm from a commercial 532 nm laser for dual-wavelength excitation. However, the fiber length for effective wavelength conversion is typically short, corresponding to a small time delay that leads to a significant overlap of the A-lines acquired at the two wavelengths. Increasing the fiber length extends the time interval but limits the pulse energy at 558 nm. In this Letter, we report a conditional generative adversarial network-based approach that enables temporal unmixing of photoacoustic A-line signals with an interval as short as ${\sim}{38}\;{\rm ns}$, breaking the physical limit on the A-line rate. Moreover, this deep learning approach allows the use of multi-spectral laser pulses for PAM excitation, addressing the insufficient energy of monochromatic laser pulses. This technique lays the foundation for ultrahigh-speed multi-parametric PAM.
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Affiliation(s)
- Yifeng Zhou
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Fenghe Zhong
- 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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24
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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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25
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Pan Y, Chen N, Liu L, Liu C, Xu Z, Zhang J. Recovery of photoacoustic images based on accurate ultrasound positioning. Vis Comput Ind Biomed Art 2021; 4:7. [PMID: 33765240 PMCID: PMC7994482 DOI: 10.1186/s42492-021-00072-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/26/2021] [Indexed: 12/02/2022] Open
Abstract
Photoacoustic microscopy is an in vivo imaging technology based on the photoacoustic effect. It is widely used in various biomedical studies because it can provide high-resolution images while being label-free, safe, and harmless to biological tissue. Polygon-scanning is an effective scanning method in photoacoustic microscopy that can realize fast imaging of biological tissue with a large field of view. However, in polygon-scanning, fluctuations of the rotating motor speed and the geometric error of the rotating mirror cause image distortions, which seriously affect the photoacoustic-microscopy imaging quality. To improve the image quality of photoacoustic microscopy using polygon-scanning, an image correction method is proposed based on accurate ultrasound positioning. In this method, the photoacoustic and ultrasound imaging data of the sample are simultaneously obtained, and the angle information of each mirror used in the polygon-scanning is extracted from the ultrasonic data to correct the photoacoustic images. Experimental results show that the proposed method can significantly reduce image distortions in photoacoustic microscopy, with the image dislocation offset decreasing from 24.774 to 10.365 μm.
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Affiliation(s)
- Yinhao Pan
- College of Mechanical and Electrical Engineering, Guangzhou University, Guangzhou, 510006, China.,Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Ningbo Chen
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Liangjian Liu
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Chengbo Liu
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Zhiqiang Xu
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Jianhui Zhang
- College of Mechanical and Electrical Engineering, Guangzhou University, Guangzhou, 510006, China.
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26
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Razansky D, Klohs J, Ni R. Multi-scale optoacoustic molecular imaging of brain diseases. Eur J Nucl Med Mol Imaging 2021; 48:4152-4170. [PMID: 33594473 PMCID: PMC8566397 DOI: 10.1007/s00259-021-05207-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/17/2021] [Indexed: 02/07/2023]
Abstract
The ability to non-invasively visualize endogenous chromophores and exogenous probes and sensors across the entire rodent brain with the high spatial and temporal resolution has empowered optoacoustic imaging modalities with unprecedented capacities for interrogating the brain under physiological and diseased conditions. This has rapidly transformed optoacoustic microscopy (OAM) and multi-spectral optoacoustic tomography (MSOT) into emerging research tools to study animal models of brain diseases. In this review, we describe the principles of optoacoustic imaging and showcase recent technical advances that enable high-resolution real-time brain observations in preclinical models. In addition, advanced molecular probe designs allow for efficient visualization of pathophysiological processes playing a central role in a variety of neurodegenerative diseases, brain tumors, and stroke. We describe outstanding challenges in optoacoustic imaging methodologies and propose a future outlook.
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Affiliation(s)
- Daniel Razansky
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Wolfgang-Pauli-Strasse 27, HIT E42.1, 8093, Zurich, Switzerland
- Zurich Neuroscience Center (ZNZ), Zurich, Switzerland
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Jan Klohs
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Wolfgang-Pauli-Strasse 27, HIT E42.1, 8093, Zurich, Switzerland
- Zurich Neuroscience Center (ZNZ), Zurich, Switzerland
| | - Ruiqing Ni
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Wolfgang-Pauli-Strasse 27, HIT E42.1, 8093, Zurich, Switzerland.
- Zurich Neuroscience Center (ZNZ), Zurich, Switzerland.
- Institute for Regenerative Medicine, Uiversity of Zurich, Zurich, Switzerland.
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27
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Jeong WY, Kang MS, Lee H, Lee JH, Kim J, Han DW, Kim KS. Recent Trends in Photoacoustic Imaging Techniques for 2D Nanomaterial-Based Phototherapy. Biomedicines 2021; 9:80. [PMID: 33467616 PMCID: PMC7830416 DOI: 10.3390/biomedicines9010080] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/13/2021] [Accepted: 01/13/2021] [Indexed: 02/06/2023] Open
Abstract
A variety of 2D materials have been developed for therapeutic biomedical studies. Because of their excellent physicochemical properties, 2D materials can be used as carriers for delivering therapeutic agents into a lesion, leading to phototherapy. Various optical imaging techniques have been used for the monitoring of the treatment process. Among these, photoacoustic imaging has unique advantages including relatively deep imaging depth and large field of view with high spatial resolution. In this review article, we summarize the types of photoacoustic imaging systems used for phototherapy monitoring, then we explore contrast-enhanced photoacoustic images using 2D materials. Finally, photoacoustic image-guided phototherapies are discussed. We conclude that 2D material-based phototherapy can be efficiently monitored by photoacoustic imaging techniques.
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Affiliation(s)
- Woo Yeup Jeong
- School of Chemical Engineering, College of Engineering, Pusan National University, Busan 46241, Korea;
| | - Moon Sung Kang
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Korea; (M.S.K.); (H.L.)
| | - Haeni Lee
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Korea; (M.S.K.); (H.L.)
| | - Jong Hun Lee
- Department of Food Science and Biotechnology, Gachon University, Seongnam, Gyeonggi 13120, Korea;
| | - Jeesu Kim
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Korea; (M.S.K.); (H.L.)
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Korea; (M.S.K.); (H.L.)
| | - Ki Su Kim
- School of Chemical Engineering, College of Engineering, Pusan National University, Busan 46241, Korea;
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28
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Yang JM, Ghim CM. Photoacoustic Tomography Opening New Paradigms in Biomedical Imaging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1310:239-341. [PMID: 33834440 DOI: 10.1007/978-981-33-6064-8_11] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
After the emergence of the ultrasound, X-ray CT, PET, and MRI, photoacoustic tomography (PAT) is now in the phase of its exponential growth, with its expected full maturation being another form of mainstream clinical imaging modality. By combining the high contrast benefit of optical imaging and the high-resolution deep imaging capability of ultrasound, PAT can provide unprecedented anatomical image contrasts at clinically relevant depths as well as enable the use of a variety of functional and molecular imaging information, which is not possible with conventional imaging modalities. With these strengths, PAT has achieved numerous breakthroughs in various biomedical applications and also provided new technical platforms that may be able to resolve unmet issues in clinics. In this chapter, we provide an overview of the development of PAT technology for several major biomedical applications and provide an approximate projection of the future of PAT.
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Affiliation(s)
- Joon-Mo Yang
- Center for Photoacoustic Medical Instruments, Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
| | - Cheol-Min Ghim
- Department of Physics, School of Natural Science, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
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29
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Das D, Sharma A, Rajendran P, Pramanik M. Another decade of photoacoustic imaging. Phys Med Biol 2020; 66. [PMID: 33361580 DOI: 10.1088/1361-6560/abd669] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/23/2020] [Indexed: 01/09/2023]
Abstract
Photoacoustic imaging - a hybrid biomedical imaging modality finding its way to clinical practices. Although the photoacoustic phenomenon was known more than a century back, only in the last two decades it has been widely researched and used for biomedical imaging applications. In this review we focus on the development and progress of the technology in the last decade (2010-2020). From becoming more and more user friendly, cheaper in cost, portable in size, photoacoustic imaging promises a wide range of applications, if translated to clinic. The growth of photoacoustic community is steady, and with several new directions researchers are exploring, it is inevitable that photoacoustic imaging will one day establish itself as a regular imaging system in the clinical practices.
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Affiliation(s)
- Dhiman Das
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Arunima Sharma
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Praveenbalaji Rajendran
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Manojit Pramanik
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, N1.3-B2-11, Singapore, 637457, SINGAPORE
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30
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Dadkhah A, Jiao S. Integrating photoacoustic microscopy with other imaging technologies for multimodal imaging. Exp Biol Med (Maywood) 2020; 246:771-777. [PMID: 33297735 DOI: 10.1177/1535370220977176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
As a hybrid optical microscopic imaging technology, photoacoustic microscopy images the optical absorption contrasts and takes advantage of low acoustic scattering of biological tissues to achieve high-resolution anatomical and functional imaging. When combined with other imaging modalities, photoacoustic microscopy-based multimodal technologies can provide complementary contrast mechanisms to reveal complementary information of biological tissues. To achieve intrinsically and precisely registered images in a multimodal photoacoustic microscopy imaging system, either the ultrasonic transducer or the light source can be shared among the different imaging modalities. These technologies are the major focus of this minireview. It also covered the progress of the recently developed penta-modal photoacoustic microscopy imaging system featuring a novel dynamic focusing technique enabled by OCT contour scan.
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Affiliation(s)
- Arash Dadkhah
- Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA
| | - Shuliang Jiao
- Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA
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31
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Estrada H, Rebling J, Hofmann U, Razansky D. Discerning calvarian microvascular networks by combined optoacoustic ultrasound microscopy. PHOTOACOUSTICS 2020; 19:100178. [PMID: 32215252 PMCID: PMC7090363 DOI: 10.1016/j.pacs.2020.100178] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 01/21/2020] [Accepted: 03/14/2020] [Indexed: 06/10/2023]
Abstract
Bone microvasculature plays a paramount role in bone marrow maintenance, development, and hematopoiesis. Studies of calvarian vascular patterns within living mammalian skull with the available intravital microscopy techniques are limited to small scale observations. We developed an optical-resolution optoacoustic microscopy method combined with ultrasound biomicroscopy in order to reveal and discern the intricate networks of calvarian and cerebral vasculature over large fields of view covering majority of the murine calvaria. The vasculature segmentation method is based on an angle-corrected homogeneous model of the rodent skull, generated using simultaneously acquired three-dimensional pulse-echo ultrasound images. The hybrid microscopy design along with the appropriate skull segmentation method enable high throughput studies of a living bone while facilitating correct anatomical interpretation of the vasculature images acquired with optical resolution optoacoustic microscopy.
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Affiliation(s)
- Héctor Estrada
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Johannes Rebling
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Urs Hofmann
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Daniel Razansky
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich and Technical University of Munich, Germany
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32
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Sun N, Ning B, Bruce AC, Cao R, Seaman SA, Wang T, Fritsche-Danielson R, Carlsson LG, Peirce SM, Hu S. In vivo imaging of hemodynamic redistribution and arteriogenesis across microvascular network. Microcirculation 2019; 27:e12598. [PMID: 31660674 DOI: 10.1111/micc.12598] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 10/17/2019] [Accepted: 10/21/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Arteriogenesis is an important mechanism that contributes to restoration of oxygen supply in chronically ischemic tissues, but remains incompletely understood due to technical limitations. This study presents a novel approach for comprehensive assessment of the remodeling pattern in a complex microvascular network containing multiple collateral microvessels. METHODS We have developed a hardware-software integrated platform for quantitative, longitudinal, and label-free imaging of network-wide hemodynamic changes and arteriogenesis at the single-vessel level. By ligating feeding arteries in the mouse ear, we induced network-wide hemodynamic redistribution and localized arteriogenesis. The utility of this technology was demonstrated by studying the influence of obesity on microvascular arteriogenesis. RESULTS Simultaneously monitoring the remodeling of competing collateral arterioles revealed a new, inverse relationship between initial vascular resistance and extent of arteriogenesis. Obese mice exhibited similar remodeling responses to lean mice through the first week, including diameter increase and flow upregulation in collateral arterioles. However, these gains were subsequently lost in obese mice. CONCLUSIONS Capable of label-free, comprehensive, and dynamic quantification of structural and functional changes in the microvascular network in vivo, this platform opens up new opportunities to study the mechanisms of microvascular arteriogenesis, its implications in diseases, and approaches to pharmacologically rectify microvascular dysfunction.
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Affiliation(s)
- Naidi Sun
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Bo Ning
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Anthony C Bruce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Scott A Seaman
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Tianxiong Wang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | | | - Leif G Carlsson
- Bioscience Heart Failure, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Shayn M Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
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Jeon S, Kim J, Lee D, Baik JW, Kim C. Review on practical photoacoustic microscopy. PHOTOACOUSTICS 2019; 15:100141. [PMID: 31463194 PMCID: PMC6710377 DOI: 10.1016/j.pacs.2019.100141] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 06/19/2019] [Accepted: 07/24/2019] [Indexed: 05/03/2023]
Abstract
Photoacoustic imaging (PAI) has many interesting advantages, such as deep imaging depth, high image resolution, and high contrast to intrinsic and extrinsic chromophores, enabling morphological, functional, and molecular imaging of living subjects. Photoacoustic microscopy (PAM) is one form of the PAI inheriting its characteristics and is useful in both preclinical and clinical research. Over the years, PAM systems have been evolved in several forms and each form has its relative advantages and disadvantages. Thus, to maximize the benefits of PAM for a specific application, it is important to configure the PAM system optimally by targeting a specific application. In this review, we provide practical methods for implementing a PAM system to improve the resolution, signal-to-noise ratio (SNR), and imaging speed. In addition, we review the preclinical and the clinical applications of PAM and discuss the current challenges and the scope for future developments.
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Affiliation(s)
| | | | | | | | - Chulhong Kim
- Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
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34
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Dadkhah A, Jiao S. Optical coherence tomography-guided dynamic focusing for combined optical and mechanical scanning multimodal photoacoustic microscopy. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-6. [PMID: 31411011 PMCID: PMC7005572 DOI: 10.1117/1.jbo.24.12.121906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/29/2019] [Indexed: 05/28/2023]
Abstract
To achieve fast imaging and large field of view (FOV), we improved our multimodal imaging system, which integrated optical resolution photoacoustic microscopy, optical coherence tomography (OCT), and confocal fluorescence microscopy in one platform, by combining optical scanning with mechanical scanning. To ensure good focusing of the objective lens over all the imaged area, we employed OCT-guided dynamic focusing. Different from our previous point-by-point dynamic focusing, we employed an area-by-area focusing adjustment strategy, in which each fast optical scanning area has a fixed focusing depth. We have demonstrated the performance of the system by imaging biological samples ex vivo (plant leaf) and in vivo (mouse ear). The system has achieved uniform resolution in an FOV of 10 mm × 10 mm with an imaging time of about 5 min.
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Affiliation(s)
- Arash Dadkhah
- Florida International University, Department of Biomedical Engineering, Miami, Florida, United States
| | - Shuliang Jiao
- Florida International University, Department of Biomedical Engineering, Miami, Florida, United States
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35
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Xu Z, Sun N, Cao R, Li Z, Liu Q, Hu S. Cortex-wide multiparametric photoacoustic microscopy based on real-time contour scanning. NEUROPHOTONICS 2019; 6:035012. [PMID: 31548975 PMCID: PMC6752259 DOI: 10.1117/1.nph.6.3.035012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/04/2019] [Indexed: 05/21/2023]
Abstract
Large-scale, high-resolution imaging of cerebral hemodynamics is essential for brain research. Uniquely capable of comprehensive quantification of cerebral hemodynamics and oxygen metabolism in rodents based on the endogenous hemoglobin contrast, multiparametric photoacoustic microscopy (PAM) is ideally suited for this purpose. However, the out-of-focus issue due to the uneven surface of the rodent brain results in inaccurate PAM measurements and presents a significant challenge to cortex-wide multiparametric recording. We report a large-scale, high-resolution, multiparametric PAM system based on real-time surface contour extraction and scanning, which avoids the prescan and offline calculation of the contour map required by previously reported contour-scanning strategies. The performance of this system has been demonstrated in both phantoms and the live mouse brain through a thinned-skull window. Side-by-side comparison shows that the real-time contour scanning not only improves the quality of structural images by addressing the out-of-focus issue but also ensures accurate measurements of the concentration of hemoglobin ( C Hb ), oxygen saturation of hemoglobin ( sO 2 ), and cerebral blood flow (CBF) over the entire mouse cortex. Furthermore, quantitative analysis reveals how the out-of-focus issue impairs the measurements of C Hb , sO 2 , and CBF.
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Affiliation(s)
- Zhiqiang Xu
- Wuhan University of Technology, School of Information Engineering, Wuhan, China
- University of Virginia, Department of Biomedical Engineering, Charlottesville, Virginia, United States
| | - Naidi Sun
- University of Virginia, Department of Biomedical Engineering, Charlottesville, Virginia, United States
| | - Rui Cao
- University of Virginia, Department of Biomedical Engineering, Charlottesville, Virginia, United States
| | - Zhengying Li
- Wuhan University of Technology, School of Information Engineering, Wuhan, China
| | - Quan Liu
- Wuhan University of Technology, School of Information Engineering, Wuhan, China
| | - Song Hu
- University of Virginia, Department of Biomedical Engineering, Charlottesville, Virginia, United States
- Address all correspondence to Song Hu, E-mail:
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36
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Cao R, Zhang C, Mitkin VV, Lankford MF, Li J, Zuo Z, Meyer CH, Goyne CP, Ahlers ST, Stone JR, Hu S. Comprehensive Characterization of Cerebrovascular Dysfunction in Blast Traumatic Brain Injury Using Photoacoustic Microscopy. J Neurotrauma 2019; 36:1526-1534. [PMID: 30501547 DOI: 10.1089/neu.2018.6062] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Blast traumatic brain injury (bTBI) is a leading contributor to combat-related injuries and death. Although substantial emphasis has been placed on blast-induced neuronal and axonal injuries, co-existing dysfunctions in the cerebral vasculature, particularly the microvasculature, remain poorly understood. Here, we studied blast-induced cerebrovascular dysfunctions in a rat model of bTBI (blast overpressure: 187.8 ± 18.3 kPa). Using photoacoustic microscopy (PAM), we quantified changes in cerebral hemodynamics and metabolism-including blood perfusion, oxygenation, flow, oxygen extraction fraction, and the metabolic rate of oxygen-4 h post-injury. Moreover, we assessed the effect of blast exposure on cerebrovascular reactivity (CVR) to vasodilatory stimulation. With vessel segmentation, we extracted these changes at the single-vessel level, revealing their dependence on vessel type (i.e., artery vs. vein) and diameter. We found that bTBI at this pressure level did not induce pronounced baseline changes in cerebrovascular diameter, blood perfusion, oxygenation, flow, oxygen extraction, and metabolism, except for a slight sO2 increase in small veins (<45 μm) and blood flow increase in large veins (≥45 μm). In contrast, this blast exposure almost abolished CVR, including arterial dilation, flow upregulation, and venous sO2 increase. This study is the most comprehensive assessment of cerebrovascular structure and physiology in response to blast exposure to date. The observed impairment in CVR can potentially cause cognitive decline due to the mismatch between cognitive metabolic demands and vessel's ability to dynamically respond to meet the demands. Also, the impaired CVR can lead to increased vulnerability of the brain to metabolic insults, including hypoxia and ischemia.
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Affiliation(s)
- Rui Cao
- 1 Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Chenchu Zhang
- 1 Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Vladimir V Mitkin
- 2 Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia
| | - Miles F Lankford
- 3 Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia
| | - Jun Li
- 4 Department of Anesthesiology, University of Virginia, Charlottesville, Virginia
| | - Zhiyi Zuo
- 4 Department of Anesthesiology, University of Virginia, Charlottesville, Virginia
| | - Craig H Meyer
- 1 Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Christopher P Goyne
- 2 Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia
| | - Stephen T Ahlers
- 5 Operational and Undersea Medicine Directorate, Naval Medical Research Center, Silver Spring, Maryland
| | - James R Stone
- 3 Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia
| | - Song Hu
- 1 Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
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37
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Zhang P, Li L, Lin L, Shi J, Wang LV. In vivo superresolution photoacoustic computed tomography by localization of single dyed droplets. LIGHT, SCIENCE & APPLICATIONS 2019; 8:36. [PMID: 30962922 PMCID: PMC6445830 DOI: 10.1038/s41377-019-0147-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 03/21/2019] [Accepted: 03/22/2019] [Indexed: 05/03/2023]
Abstract
Photoacoustic (PA) computed tomography (PACT) is a noninvasive hybrid imaging technique that combines optical excitation and acoustic detection to realize high contrast, high resolution, and deep penetration in biological tissues. However, the spatial resolution of PACT is limited by acoustic diffraction. Here, we report in vivo superresolution PACT, which breaks the acoustic diffraction limit by localizing the centers of single dyed droplets that are flowing in blood vessels. The droplets were prepared by dissolving hydrophobic absorbing dye in oil, followed by mixing with water. The dyed droplets generate much higher-amplitude PA signals than blood and can flow smoothly in vessels; thus, they are excellent tracers for localization-based superresolution imaging. The in vivo resolution enhancement was demonstrated by continuously imaging the cortical layer of a mouse brain during droplet injection. The droplets that were flowing in the vessels were localized, and their center positions were used to construct a superresolution image that exhibits sharper features and more finely resolved vascular details. An improvement in spatial resolution by a factor of 6 has been realized in vivo by the droplet localization technique.
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Affiliation(s)
- Pengfei Zhang
- Optical Imaging Laboratory, Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130 USA
- Present Address: School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, 300072 China
| | - Lei Li
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, California Institute of Technology, 1200 E. California Blvd., MC 138-78, Pasadena, CA 91125 USA
| | - Li Lin
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, California Institute of Technology, 1200 E. California Blvd., MC 138-78, Pasadena, CA 91125 USA
| | - Junhui Shi
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, California Institute of Technology, 1200 E. California Blvd., MC 138-78, Pasadena, CA 91125 USA
| | - Lihong V. Wang
- Caltech Optical Imaging Laboratory, Andrew and Peggy Cherng Department of Medical Engineering, Department of Electrical Engineering, California Institute of Technology, 1200 E. California Blvd., MC 138-78, Pasadena, CA 91125 USA
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Dadkhah A, Zhou J, Yeasmin N, Jiao S. Integrated multimodal photoacoustic microscopy with OCT- guided dynamic focusing. BIOMEDICAL OPTICS EXPRESS 2019; 10:137-150. [PMID: 30775089 PMCID: PMC6363202 DOI: 10.1364/boe.10.000137] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/27/2018] [Accepted: 11/27/2018] [Indexed: 05/10/2023]
Abstract
Combining different contrast mechanisms to achieve simultaneous multimodal imaging is always desirable but is challenging due to the various optical and hardware requirements for different imaging systems. We developed a multimodal microscopic optical imaging system with the capability of providing comprehensive structural, functional and molecular information of living tissues. This imaging system integrated photoacoustic microscopy (PAM), optical coherence tomography (OCT), optical Doppler tomography (ODT) and confocal fluorescence microscopy in one platform. By taking advantage of the depth resolving capability of OCT, we developed a novel OCT-guided surface contour scanning methodology for dynamic focusing adjustment. We have conducted phantom, in vivo, and ex vivo tests to demonstrate the capability of the multimodal imaging system for providing comprehensive microscopic information of biological tissues. Integrating all the aforementioned imaging modalities with OCT-guided dynamic focusing for simultaneous multimodal imaging has promising potential for preclinical research and clinical practice in the future.
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Affiliation(s)
- Arash Dadkhah
- Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA
| | - Jun Zhou
- School of Physics and Information Engineering, Jianghan University, Wuhan, Hubei 430056, China
| | - Nusrat Yeasmin
- Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA
| | - Shuliang Jiao
- Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA
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39
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Wang T, Sun N, Chen R, Zhou Q, Hu S. Isotropic-resolution photoacoustic microscopy with multi-angle illumination. OPTICS LETTERS 2019; 44:1-4. [PMID: 30645542 PMCID: PMC6422037 DOI: 10.1364/ol.44.000001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 11/13/2018] [Indexed: 05/29/2023]
Abstract
We have developed photoacoustic microscopy (PAM) with three-dimensional (3D) micron-level spatial resolution. With multi-angle illumination, PAM images from different view angles can be simultaneously acquired for multi-view deconvolution, without the rotation of imaging targets. A side-by-side comparison of this multi-angle-illumination PAM (MAI-PAM) and conventional PAM, which share the same ultrasonic detector, was performed in phantoms and live mice. The phantom study showed that MAI-PAM achieved a high axial resolution of 3.7 μm, which was 10-fold higher than that of conventional PAM and approached the lateral resolution of 2.7 μm. Furthermore, the in vivo study demonstrated that MAI-PAM was able to image the 3D microvasculature with isotropic spatial resolution.
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Affiliation(s)
- Tianxiong Wang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Naidi Sun
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Ruimin Chen
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA
| | - Qifa Zhou
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA
- Department of Ophthalmology, University of Southern California, Los Angeles, California 90089, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
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40
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Cao R, Li J, Zhang C, Zuo Z, Hu S. Photoacoustic microscopy of obesity-induced cerebrovascular alterations. Neuroimage 2018; 188:369-379. [PMID: 30553918 DOI: 10.1016/j.neuroimage.2018.12.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 12/05/2018] [Accepted: 12/12/2018] [Indexed: 12/14/2022] Open
Abstract
Cerebral small vessel disease has been linked to cognitive, psychiatric and physical disabilities, especially in the elderly. However, the underlying pathophysiology remains incompletely understood, largely due to the limited accessibility of these small vessels in the live brain. Here, we report an intravital imaging and analysis platform for high-resolution, quantitative and comprehensive characterization of pathological alterations in the mouse cerebral microvasculature. By exploiting multi-parametric photoacoustic microscopy (PAM), microvascular structure, blood perfusion, oxygenation and flow were imaged in the awake brain. With the aid of vessel segmentation, these structural and functional parameters were extracted at the single-microvessel level, from which vascular density, tortuosity, wall shear stress, resistance and associated cerebral oxygen extraction fraction and metabolism were also quantified. With the use of vasodilatory stimulus, multifaceted cerebrovascular reactivity (CVR) was characterized in vivo. By extending the classic Evans blue assay to in vivo, permeability of the blood-brain barrier (BBB) was dynamically evaluated. The utility of this enabling technique was examined by studying cerebrovascular alterations in an established mouse model of high-fat diet-induced obesity. Our results revealed increased vascular density, reduced arterial flow, enhanced oxygen extraction, impaired BBB integrity, and increased multifaceted CVR in the obese brain. Interestingly, the 'counterintuitive' increase of CVR was supported by the elevated active endothelial nitric oxide synthase in the obese mouse. Providing comprehensive and quantitative insights into cerebral microvessels and their responses under pathological conditions, this technique opens a new door to mechanistic studies of the cerebral small vessel disease and its implications in neurodegeneration and stroke.
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Affiliation(s)
- Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA
| | - Jun Li
- Department of Anesthesiology, University of Virginia, Charlottesville, USA
| | - Chenchu Zhang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, Charlottesville, USA.
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA.
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41
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Cao R, Li J, Kharel Y, Zhang C, Morris E, Santos WL, Lynch KR, Zuo Z, Hu S. Photoacoustic microscopy reveals the hemodynamic basis of sphingosine 1-phosphate-induced neuroprotection against ischemic stroke. Theranostics 2018; 8:6111-6120. [PMID: 30613286 PMCID: PMC6299683 DOI: 10.7150/thno.29435] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/12/2018] [Indexed: 12/22/2022] Open
Abstract
Rationale: Emerging evidence has suggested that sphingosine 1-phosphate (S1P), a bioactive metabolite of sphingolipids, may play an important role in the pathophysiological processes of cerebral hypoxia and ischemia. However, the influence of S1P on cerebral hemodynamics and metabolism remains unclear. Material and Methods: Uniquely capable of high-resolution, label-free, and comprehensive imaging of hemodynamics and oxygen metabolism in the mouse brain without the influence of general anesthesia, our newly developed head-restrained multi-parametric photoacoustic microscopy (PAM) is well suited for this mechanistic study. Here, combining the cutting-edge PAM and a selective inhibitor of sphingosine kinase 2 (SphK2) that can increase the blood S1P level, we investigated the role of S1P in cerebral oxygen supply-demand and its neuroprotective effects on global brain hypoxia induced by nitrogen gas inhalation and focal brain ischemia induced by transient middle cerebral artery occlusion (tMCAO). Results: Inhibition of SphK2, which increased the blood S1P, resulted in the elevation of both arterial and venous sO2 in the hypoxic mouse brain, while the cerebral blood flow remained unchanged. As a result, it gradually and significantly reduced the metabolic rate of oxygen. Furthermore, pre-treatment of the mice subject to tMCAO with the SphK2 inhibitor led to decreased infarct volume, improved motor function, and reduced neurological deficit, compared to the control treatment with a less potent R-enantiomer. In contrast, post-treatment with the inhibitor showed no improvement in the stroke outcomes. The failure for the post-treatment to induce neuroprotection was likely due to the relatively slow hemodynamic responses to the SphK2 inhibitor-evoked S1P intervention, which did not take effect before the brain injury was induced. Conclusions: Our results reveal that elevated blood S1P significantly changes cerebral hemodynamics and oxygen metabolism under hypoxia but not normoxia. The improved blood oxygenation and reduced oxygen demand in the hypoxic brain may underlie the neuroprotective effect of S1P against ischemic stroke.
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Affiliation(s)
- Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA
| | - Jun Li
- Department of Anesthesiology, University of Virginia, Charlottesville, USA
| | - Yugesh Kharel
- Department of Pharmacology, University of Virginia, Charlottesville, USA
| | - Chenchu Zhang
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA
| | - Emily Morris
- Department of Chemistry and VT Center for Drug Discovery, Virginia Tech, Blacksburg, USA
| | - Webster L. Santos
- Department of Chemistry and VT Center for Drug Discovery, Virginia Tech, Blacksburg, USA
| | - Kevin R. Lynch
- Department of Pharmacology, University of Virginia, Charlottesville, USA
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, Charlottesville, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, USA
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42
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Norambuena A, Wallrabe H, Cao R, Wang DB, Silva A, Svindrych Z, Periasamy A, Hu S, Tanzi RE, Kim DY, Bloom GS. A novel lysosome-to-mitochondria signaling pathway disrupted by amyloid-β oligomers. EMBO J 2018; 37:embj.2018100241. [PMID: 30348864 DOI: 10.15252/embj.2018100241] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/30/2018] [Accepted: 09/05/2018] [Indexed: 12/31/2022] Open
Abstract
The mechanisms of mitochondrial dysfunction in Alzheimer's disease are incompletely understood. Using two-photon fluorescence lifetime microscopy of the coenzymes, NADH and NADPH, and tracking brain oxygen metabolism with multi-parametric photoacoustic microscopy, we show that activation of lysosomal mechanistic target of rapamycin complex 1 (mTORC1) by insulin or amino acids stimulates mitochondrial activity and regulates mitochondrial DNA synthesis in neurons. Amyloid-β oligomers, which are precursors of amyloid plaques in Alzheimer's disease brain and stimulate mTORC1 protein kinase activity at the plasma membrane but not at lysosomes, block this Nutrient-induced Mitochondrial Activity (NiMA) by a mechanism dependent on tau, which forms neurofibrillary tangles in Alzheimer's disease brain. NiMA was also disrupted in fibroblasts derived from two patients with tuberous sclerosis complex, a genetic disorder that causes dysregulation of lysosomal mTORC1. Thus, lysosomal mTORC1 couples nutrient availability to mitochondrial activity and links mitochondrial dysfunction to Alzheimer's disease by a mechanism dependent on the soluble building blocks of the poorly soluble plaques and tangles.
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Affiliation(s)
- Andrés Norambuena
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Horst Wallrabe
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Dora Bigler Wang
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Antonia Silva
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Zdenek Svindrych
- Department of Biology, University of Virginia, Charlottesville, VA, USA.,W.M. Keck Center for Cellular Imaging, University of Virginia, Charlottesville, VA, USA
| | - Ammasi Periasamy
- Department of Biology, University of Virginia, Charlottesville, VA, USA.,W.M. Keck Center for Cellular Imaging, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Disease, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| | - Doo Yeon Kim
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Disease, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| | - George S Bloom
- Department of Biology, University of Virginia, Charlottesville, VA, USA .,Department of Cell Biology, University of Virginia, Charlottesville, VA, USA.,Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
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43
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Louveau A, Herz J, Alme MN, Salvador AF, Dong MQ, Viar KE, Herod SG, Knopp J, Setliff JC, Lupi AL, Da Mesquita S, Frost EL, Gaultier A, Harris TH, Cao R, Hu S, Lukens JR, Smirnov I, Overall CC, Oliver G, Kipnis J. CNS lymphatic drainage and neuroinflammation are regulated by meningeal lymphatic vasculature. Nat Neurosci 2018; 21:1380-1391. [PMID: 30224810 PMCID: PMC6214619 DOI: 10.1038/s41593-018-0227-9] [Citation(s) in RCA: 552] [Impact Index Per Article: 92.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 08/02/2018] [Indexed: 12/25/2022]
Abstract
Neuroinflammatory diseases, such as multiple sclerosis, are characterized by invasion of the brain by autoreactive T cells. The mechanism for how T cells acquire their encephalitogenic phenotype and trigger disease remains, however, unclear. The existence of lymphatic vessels in the meninges indicates a relevant link between the CNS and peripheral immune system, perhaps affecting autoimmunity. Here we demonstrate that meningeal lymphatics fulfill two critical criteria: they assist in the drainage of cerebrospinal fluid components and enable immune cells to enter draining lymph nodes in a CCR7-dependent manner. Unlike other tissues, meningeal lymphatic endothelial cells do not undergo expansion during inflammation, and they express a unique transcriptional signature. Notably, the ablation of meningeal lymphatics diminishes pathology and reduces the inflammatory response of brain-reactive T cells during an animal model of multiple sclerosis. Our findings demonstrate that meningeal lymphatics govern inflammatory processes and immune surveillance of the CNS and pose a valuable target for therapeutic intervention.
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Affiliation(s)
- Antoine Louveau
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA.
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
| | - Jasmin Herz
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Maria Nordheim Alme
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Andrea Francesca Salvador
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Michael Q Dong
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Kenneth E Viar
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - S Grace Herod
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - James Knopp
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Joshua C Setliff
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Alexander L Lupi
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Sandro Da Mesquita
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Elizabeth L Frost
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Alban Gaultier
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Tajie H Harris
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - John R Lukens
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Igor Smirnov
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Christopher C Overall
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Guillermo Oliver
- Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Jonathan Kipnis
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA.
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA.
- Gutenberg Research Fellowship Group of Neuroimmunology, Focus Program Translational Neuroscience (FTN) and Immunotherapy (FZI), Rhine Main Neuroscience Network (rmn²), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
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44
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Rebling J, Estrada H, Gottschalk S, Sela G, Zwack M, Wissmeyer G, Ntziachristos V, Razansky D. Dual-wavelength hybrid optoacoustic-ultrasound biomicroscopy for functional imaging of large-scale cerebral vascular networks. JOURNAL OF BIOPHOTONICS 2018; 11:e201800057. [PMID: 29675962 DOI: 10.1002/jbio.201800057] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/18/2018] [Indexed: 05/03/2023]
Abstract
A critical link exists between pathological changes of cerebral vasculature and diseases affecting brain function. Microscopic techniques have played an indispensable role in the study of neurovascular anatomy and functions. Yet, investigations are often hindered by suboptimal trade-offs between the spatiotemporal resolution, field-of-view (FOV) and type of contrast offered by the existing optical microscopy techniques. We present a hybrid dual-wavelength optoacoustic (OA) biomicroscope capable of rapid transcranial visualization of large-scale cerebral vascular networks. The system offers 3-dimensional views of the morphology and oxygenation status of the cerebral vasculature with single capillary resolution and a FOV exceeding 6 × 8 mm2 , thus covering the entire cortical vasculature in mice. The large-scale OA imaging capacity is complemented by simultaneously acquired pulse-echo ultrasound (US) biomicroscopy scans of the mouse skull. The new approach holds great potential to provide better insights into cerebrovascular function and facilitate efficient studies into neurological and vascular abnormalities of the brain.
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Affiliation(s)
- Johannes Rebling
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
- Faculty of Medicine and Faculty of Electrical Engineering, Technical University of Munich, München, Germany
| | - Héctor Estrada
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Sven Gottschalk
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Gali Sela
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Michael Zwack
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Georg Wissmeyer
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
- Faculty of Medicine and Faculty of Electrical Engineering, Technical University of Munich, München, Germany
| | - Vasilis Ntziachristos
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
- Faculty of Medicine and Faculty of Electrical Engineering, Technical University of Munich, München, Germany
| | - Daniel Razansky
- Institute of Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
- Faculty of Medicine and Faculty of Electrical Engineering, Technical University of Munich, München, Germany
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45
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Da Mesquita S, Louveau A, Vaccari A, Smirnov I, Cornelison RC, Kingsmore KM, Contarino C, Onengut-Gumuscu S, Farber E, Raper D, Viar KE, Powell RD, Baker W, Dabhi N, Bai R, Cao R, Hu S, Rich SS, Munson JM, Lopes MB, Overall CC, Acton ST, Kipnis J. Functional aspects of meningeal lymphatics in ageing and Alzheimer's disease. Nature 2018; 560:185-191. [PMID: 30046111 PMCID: PMC6085146 DOI: 10.1038/s41586-018-0368-8] [Citation(s) in RCA: 786] [Impact Index Per Article: 131.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 06/15/2018] [Indexed: 01/26/2023]
Abstract
Ageing is a major risk factor for many neurological pathologies, but its mechanisms remain unclear. Unlike other tissues, the parenchyma of the central nervous system (CNS) lacks lymphatic vasculature and waste products are removed partly through a paravascular route. (Re)discovery and characterization of meningeal lymphatic vessels has prompted an assessment of their role in waste clearance from the CNS. Here we show that meningeal lymphatic vessels drain macromolecules from the CNS (cerebrospinal and interstitial fluids) into the cervical lymph nodes in mice. Impairment of meningeal lymphatic function slows paravascular influx of macromolecules into the brain and efflux of macromolecules from the interstitial fluid, and induces cognitive impairment in mice. Treatment of aged mice with vascular endothelial growth factor C enhances meningeal lymphatic drainage of macromolecules from the cerebrospinal fluid, improving brain perfusion and learning and memory performance. Disruption of meningeal lymphatic vessels in transgenic mouse models of Alzheimer's disease promotes amyloid-β deposition in the meninges, which resembles human meningeal pathology, and aggravates parenchymal amyloid-β accumulation. Meningeal lymphatic dysfunction may be an aggravating factor in Alzheimer's disease pathology and in age-associated cognitive decline. Thus, augmentation of meningeal lymphatic function might be a promising therapeutic target for preventing or delaying age-associated neurological diseases.
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Affiliation(s)
- Sandro Da Mesquita
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA.
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
| | - Antoine Louveau
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Andrea Vaccari
- Virginia Image and Video Analysis Laboratory, Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Igor Smirnov
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - R Chase Cornelison
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Kathryn M Kingsmore
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Christian Contarino
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
- Department of Mathematics, University of Trento, Povo, Italy
| | - Suna Onengut-Gumuscu
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Emily Farber
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Daniel Raper
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
- Department of Neurosurgery, University of Virginia Health System, Charlottesville, VA, USA
| | - Kenneth E Viar
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Romie D Powell
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Wendy Baker
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Nisha Dabhi
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Robin Bai
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Rui Cao
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Jennifer M Munson
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering and Mechanics, College of Engineering, Virginia Tech, Blacksburg, VA, USA
| | - M Beatriz Lopes
- Department of Pathology, University of Virginia, Charlottesville, VA, USA
| | - Christopher C Overall
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Scott T Acton
- Virginia Image and Video Analysis Laboratory, Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Jonathan Kipnis
- Center for Brain Immunology and Glia (BIG), University of Virginia, Charlottesville, VA, USA.
- Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
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46
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Chuangsuwanich T, Moothanchery M, Tsz Chung Yan A, Schmetterer L, Girard MJA, Pramanik M. Photoacoustic imaging of lamina cribrosa microcapillaries in porcine eyes. APPLIED OPTICS 2018; 57:4865-4871. [PMID: 30118104 DOI: 10.1364/ao.57.004865] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 05/17/2018] [Indexed: 05/18/2023]
Abstract
Due to the embedded nature of the lamina cribrosa (LC) microcapillary network, conventional imaging techniques have failed to obtain the high-resolution images needed to assess the perfusion state of the LC. In this study, both optical resolution (OR) and acoustic resolution (AR) photoacoustic microscopy (PAM) techniques were used to obtain static and dynamic information about LC perfusion in ex vivo porcine eyes. The OR-PAM system could resolve a perfused LC microcapillary network with a lateral resolution of 4.2 μm and also provided good depth information (33 μm axial resolution) to visualize through-thickness vascular variations. The AR-PAM system was capable of detecting time-dependent perfusion variations. This study represents the first step towards using an emerging imaging modality (PAM) to study the LC's perfusion, which could be a basis for further investigation of the hemodynamic aspects of glaucomatous optic neuropathy.
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47
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Luo X, Peng K, Wang B, Wang T, Xiao J. [Focal zone integral and multiple axial scanning based acoustic resolution photoacoustic microscopy with high lateral resolution in-depth]. SHENG WU YI XUE GONG CHENG XUE ZA ZHI = JOURNAL OF BIOMEDICAL ENGINEERING = SHENGWU YIXUE GONGCHENGXUE ZAZHI 2018; 35:115-122. [PMID: 29745610 PMCID: PMC10307544 DOI: 10.7507/1001-5515.201609072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Indexed: 06/08/2023]
Abstract
Acoustic resolution photoacoustic microscopy (ARPAM) combines the advantages of high optical contrast, and high ultrasonic spatial resolution and penetration. However, in photoacoustic microscopy (PAM), the information from deep regions can be greatly affected by the shallow targets, and most importantly, the irreconcilable conflict between the lateral resolution and depth of fields has always be a major factor that limits the imaging quality. In this work, an ARPAM system was developed, in which a non-coaxial arrangement of light illumination and acoustic detection was adopted to alleviate the influence of the tissue surface on the deep targets, and a novel focal zone integral algorithm was applied with multiple axial scanning to improve the lateral resolution. Phantom experiment results show that, the build system can maintain a consistent high lateral resolution of 0.6 mm over a large range in axial direction, which is close to the theoretical calculations. The following tumor imaging results on nude mice indicate that, the proposed method can provide more in-depth information compared with the conventional back detection ARPAM method. With the development of fast repetition lasers and image scanning technologies, the proposed method may play an important role in cerebral vascular imaging, cervical cancer photoacoustic endoscopic detection, and superficial tumor imaging.
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Affiliation(s)
- Xiaofei Luo
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha 410083, P.R.China
| | - Kuan Peng
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha 410083, P.R.China
| | - Bo Wang
- College of Biology, Hunan University, Changsha 410082, P.R.China
| | - Tianshuang Wang
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha 410083, P.R.China
| | - Jiaying Xiao
- Department of Biomedical Engineering, School of Basic Medical Science, Central South University, Changsha 410083,
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48
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Estrada H, Huang X, Rebling J, Zwack M, Gottschalk S, Razansky D. Virtual craniotomy for high-resolution optoacoustic brain microscopy. Sci Rep 2018; 8:1459. [PMID: 29362486 PMCID: PMC5780415 DOI: 10.1038/s41598-017-18857-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 12/12/2017] [Indexed: 01/23/2023] Open
Abstract
Ultrasound-mediated transcranial images of the brain often suffer from acoustic distortions produced by the skull bone. In high-resolution optoacoustic microscopy, the skull-induced acoustic aberrations are known to impair image resolution and contrast, further skewing the location and intensity of the different absorbing structures. We present a virtual craniotomy deconvolution algorithm based on an ultrasound wave propagation model that corrects for the skull-induced distortions in optically-resolved optoacoustic transcranial microscopy data. The method takes advantage of the geometrical and spectral information of a pulse-echo ultrasound image of the skull simultaneously acquired by our multimodal imaging system. Transcranial mouse brain imaging experiments confirmed the ability to accurately account for the signal amplitude decay, temporal delay and pulse broadening introduced by the rodent's skull. Our study is the first to demonstrate skull-corrected transcranial optoacoustic imaging in vivo.
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Affiliation(s)
- Héctor Estrada
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany.
| | - Xiao Huang
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Johannes Rebling
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
- School of Medicine and School of Bioengineering, Technical University of Munich, Munich, Germany
| | - Michael Zwack
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Sven Gottschalk
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany
| | - Daniel Razansky
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Neuherberg, Germany.
- School of Medicine and School of Bioengineering, Technical University of Munich, Munich, Germany.
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49
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Identification of the S100 fused-type protein hornerin as a regulator of tumor vascularity. Nat Commun 2017; 8:552. [PMID: 28916756 PMCID: PMC5601918 DOI: 10.1038/s41467-017-00488-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 07/04/2017] [Indexed: 02/03/2023] Open
Abstract
Sustained angiogenesis is essential for the development of solid tumors and metastatic disease. Disruption of signaling pathways that govern tumor vascularity provide a potential avenue to thwart cancer progression. Through phage display-based functional proteomics, immunohistochemical analysis of human pancreatic ductal carcinoma (PDAC) specimens, and in vitro validation, we reveal that hornerin, an S100 fused-type protein, is highly expressed on pancreatic tumor endothelium in a vascular endothelial growth factor (VEGF)-independent manner. Murine-specific hornerin knockdown in PDAC xenografts results in tumor vessels with decreased radii and tortuosity. Hornerin knockdown tumors have significantly reduced leakiness, increased oxygenation, and greater apoptosis. Additionally, these tumors show a significant reduction in growth, a response that is further heightened when therapeutic inhibition of VEGF receptor 2 (VEGFR2) is utilized in combination with hornerin knockdown. These results indicate that hornerin is highly expressed in pancreatic tumor endothelium and alters tumor vessel parameters through a VEGF-independent mechanism.Angiogenesis is essential for solid tumor progression. Here, the authors interrogate the proteome of pancreatic cancer endothelium via phage display and identify hornerin as a critical protein whose expression is essential to maintain the pancreatic cancer vasculature through a VEGF-independent mechanism.
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50
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Dynamic, heterogeneous endothelial Tie2 expression and capillary blood flow during microvascular remodeling. Sci Rep 2017; 7:9049. [PMID: 28831080 PMCID: PMC5567377 DOI: 10.1038/s41598-017-08982-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/20/2017] [Indexed: 12/20/2022] Open
Abstract
Microvascular endothelial cell heterogeneity and its relationship to hemodynamics remains poorly understood due to a lack of sufficient methods to examine these parameters in vivo at high resolution throughout an angiogenic network. The availability of surrogate markers for functional vascular proteins, such as green fluorescent protein, enables expression in individual cells to be followed over time using confocal microscopy, while photoacoustic microscopy enables dynamic measurement of blood flow across the network with capillary-level resolution. We combined these two non-invasive imaging modalities in order to spatially and temporally analyze biochemical and biomechanical drivers of angiogenesis in murine corneal neovessels. By stimulating corneal angiogenesis with an alkali burn in Tie2-GFP fluorescent-reporter mice, we evaluated how onset of blood flow and surgically-altered blood flow affects Tie2-GFP expression. Our study establishes a novel platform for analyzing heterogeneous blood flow and fluorescent reporter protein expression across a dynamic microvascular network in an adult mammal.
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