1
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Chen X, Ma Z, Wang C, Cui J, Fan F, Gao X, Zhu J. Motion Artifact Correction for OCT Microvascular Images Based on Image Feature Matching. JOURNAL OF BIOPHOTONICS 2024:e202400198. [PMID: 39198156 DOI: 10.1002/jbio.202400198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/11/2024] [Accepted: 07/27/2024] [Indexed: 09/01/2024]
Abstract
Optical coherence tomography angiography (OCTA), a functional extension of optical coherence tomography (OCT), is widely employed for high-resolution imaging of microvascular networks. However, due to the relatively low scan rate of OCT, the artifacts caused by the involuntary bulk motion of tissues severely impact the visualization of microvascular networks. This study proposes a fast motion correction method based on image feature matching for OCT microvascular images. First, the rigid motion-related mismatch between B-scans is compensated through the image feature matching based on the improved oriented FAST and rotated BRIEF algorithm. Then, the axial motion within A-scan lines in each B-scan image is corrected according to the displacement deviation between the detected boundaries achieved by the Scharr operator in a non-rigid transformation manner. Finally, an optimized intensity-based Doppler variance algorithm is developed to enhance the robustness of the OCTA imaging. The experimental results demonstrate the effectiveness of the method.
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Affiliation(s)
- Xudong Chen
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Zongqing Ma
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Chongyang Wang
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Jiaqi Cui
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Fan Fan
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
| | - Xinxiao Gao
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Jiang Zhu
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
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2
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Xie Z, Shi Y, Marmin A, Wang RK. Investigation of the Effect of Compression Pressure in Contact OCT Imaging on the Measurement of Epidermis Thickness. JOURNAL OF BIOPHOTONICS 2024:e202400289. [PMID: 39191514 DOI: 10.1002/jbio.202400289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/24/2024] [Accepted: 07/31/2024] [Indexed: 08/29/2024]
Abstract
Optical coherence tomography (OCT) is a noninvasive 3D imaging technique that offers significant advantages over traditional microscopy and biopsy in measuring epidermal thickness (ET) when assessing skin conditions. However, OCT imagining is often required to be in a contact mode for mitigating the issues of subject movement and uneven skin topology. It is not known whether the contact would affect the ability of ET measurements. In this study, we investigate the relationship between the contact pressure applied and the ET measurements. We observed progressive deformation in the epidermis with the increase of compression forces, where a notable decrease of up to 13% in ET measurement and 70% decrease in capillary vessels was noted when imaging was in contact mode. We also observed 8.1% less deformation properties in scar tissue than in nearby healthy tissue. Our study underscored the importance of controlled pressure in contact imaging mode, which is often neglected.
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Affiliation(s)
- Zhiying Xie
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Yaping Shi
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Agathe Marmin
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
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3
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Nagy BI, Mohos B, Tzou CHJ. Imaging Modalities for Evaluating Lymphedema. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:2016. [PMID: 38004065 PMCID: PMC10673374 DOI: 10.3390/medicina59112016] [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: 09/09/2023] [Revised: 10/18/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023]
Abstract
Lymphedema is a progressive condition. Its therapy aims to reduce edema, prevent its progression, and provide psychosocial aid. Nonsurgical treatment in advanced stages is mostly insufficient. Therefore-in many cases-surgical procedures, such as to restore lymph flow or excise lymphedema tissues, are the only ways to improve patients' quality of life. Imaging modalities: Lymphoscintigraphy (LS), near-infrared fluorescent (NIRF) imaging-also termed indocyanine green (ICG) lymphography (ICG-L)-ultrasonography (US), magnetic resonance lymphangiography (MRL), computed tomography (CT), photoacoustic imaging (PAI), and optical coherence tomography (OCT) are standardized techniques, which can be utilized in lymphedema diagnosis, staging, treatment, and follow-up. Conclusions: The combined use of these imaging modalities and self-assessment questionnaires deliver objective parameters for choosing the most suitable surgical therapy and achieving the best possible postoperative outcome.
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Affiliation(s)
- Bendeguz Istvan Nagy
- Department of Thoracic, Cardiac and Vascular Surgery, Westpfalz-Klinikum GmbH, 67655 Kaiserslautern, Germany
| | - Balazs Mohos
- Heart and Vascular Center, Semmelweis University, 1094 Budapest, Hungary
- Plastic and Reconstructive Surgery, Department of Surgery, County Hospital Veszprem, 8200 Veszprem, Hungary
- Balaton Private Clinic, 8200 Veszprem, Hungary
| | - Chieh-Han John Tzou
- Plastic and Reconstructive Surgery, Department of Surgery, Hospital of Divine Savior, 1060 Vienna, Austria
- Faculty of Medicine, Sigmund Freud University, 1020 Vienna, Austria
- Lymphedema Center Vienna, TZOU MEDICAL., 1060 Vienna, Austria
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4
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Wang M, Singh R, Zhang W, Orringer JS, Paulus YM, Yang X, Wang X. Cutaneous Hypervascularization Treatment Using Photo-Mediated Ultrasound Therapy. JID INNOVATIONS 2023; 3:100237. [PMID: 38024557 PMCID: PMC10661455 DOI: 10.1016/j.xjidi.2023.100237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 12/01/2023] Open
Abstract
Photo-mediated ultrasound therapy (PUT) is a cavitation-based, highly selective antivascular technique. In this study, the effectiveness and safety of PUT on cutaneous vascular malformation was examined through in vivo experiments in a clinically relevant chicken wattle model, whose microanatomy is similar to that of port-wine stain and other hypervascular dermal diseases in humans. Assessed by optical coherence tomography angiography, the blood vessel density in the chicken wattle decreased by 73.23% after one session of PUT treatment in which 0.707 J/cm2 fluence laser pulses were applied concurrently with ultrasound bursts (n = 7, P < .01). The effectiveness of removing blood vessels in the skin at depth up to 1 mm was further assessed by H&E-stained histology at multiple time points, which included days 1, 3, 7, 14, and 21 after treatment. Additional immunohistochemical analyses with CD31, caspase-3, and Masson's trichrome stains were performed on day 3 after treatment. The results show that the PUT-induced therapeutic effect was confined and specific to blood vessels only, whereas unwanted collateral damage in other skin tissues such as collagen was avoided. The findings from this study demonstrate that PUT can efficiently and safely remove hypervascular dermal capillaries using laser fluence at a level that is orders of magnitude smaller than that used in conventional laser treatment of vascular lesions, thus offering a safer alternative technique for clinical management of cutaneous vascular malformations.
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Affiliation(s)
- Mingyang Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Rohit Singh
- PhotoSonoX LLC, Ann Arbor, Michigan, USA
- Institute for Bioengineering Research, University of Kansas, Lawrence, Kansas, USA
- Department of Mechanical Engineering, School of Engineering, University of Kansas, Lawrence, Kansas, USA
| | - Wei Zhang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Yannis M. Paulus
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Xinmai Yang
- Institute for Bioengineering Research, University of Kansas, Lawrence, Kansas, USA
- Department of Mechanical Engineering, School of Engineering, University of Kansas, Lawrence, Kansas, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
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5
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Dominguez CT, Martinelli MB, Bachmann L, Cardoso GC. Arterial pulsation modulates the optical attenuation coefficient of skin. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2023; 40:C87-C92. [PMID: 37132976 DOI: 10.1364/josaa.482939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Photoplethysmographic (PPG) signals arise from the modulation of light reflectivity on the skin due to changes of physiological origin. Imaging plethysmography (iPPG) is a video-based PPG method that can remotely monitor vital signs in a non-invasive manner. iPPG signals result from skin reflectivity modulation. The origin of such reflectivity modulation is still a subject of debate. Here, we have used optical coherence tomography (OCT) imaging to find whether iPPG signals may result from skin optical properties being directly or indirectly modulated by arterial transmural pressure propagation. The light intensity across the tissue was modeled through a simple exponential decay (Beer-Lambert law) to analyze in vivo the modulation of the optical attenuation coefficient of the skin by arterial pulsation. The OCT transversal images were acquired from a forearm of three subjects in a pilot study. The results show that the optical attenuation coefficient of skin changes at the same frequency as the arterial pulsation due to transmural pressure propagation (local ballistographic effect), but we cannot discard the contribution of global ballistographic effects.
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6
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Mirg S, Turner KL, Chen H, Drew PJ, Kothapalli SR. Photoacoustic imaging for microcirculation. Microcirculation 2022; 29:e12776. [PMID: 35793421 PMCID: PMC9870710 DOI: 10.1111/micc.12776] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/13/2022] [Accepted: 06/28/2022] [Indexed: 01/26/2023]
Abstract
Microcirculation facilitates the blood-tissue exchange of nutrients and regulates blood perfusion. It is, therefore, essential in maintaining tissue health. Aberrations in microcirculation are potentially indicative of underlying cardiovascular and metabolic pathologies. Thus, quantitative information about it is of great clinical relevance. Photoacoustic imaging (PAI) is a capable technique that relies on the generation of imaging contrast via the absorption of light and can image at micron-scale resolution. PAI is especially desirable to map microvasculature as hemoglobin strongly absorbs light and can generate a photoacoustic signal. This paper reviews the current state of the art for imaging microvascular networks using photoacoustic imaging. We further describe how quantitative information about blood dynamics such as the total hemoglobin concentration, oxygen saturation, and blood flow rate is obtained using PAI. We also discuss its importance in understanding key pathophysiological processes in neurovascular, cardiovascular, ophthalmic, and cancer research fields. We then discuss the current challenges and limitations of PAI and the approaches that can help overcome these limitations. Finally, we provide the reader with an overview of future trends in the field of PAI for imaging microcirculation.
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Affiliation(s)
- Shubham Mirg
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Kevin L. Turner
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Haoyang Chen
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA,Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Patrick J. Drew
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA,Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, USA,Department of Neurosurgery, Pennsylvania State University, University Park, PA 16802, USA,Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Sri-Rajasekhar Kothapalli
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA,Penn State Cancer Institute, Pennsylvania State University, Hershey, PA 17033, USA,Graduate Program in Acoustics, Pennsylvania State University, University Park, PA 16802, USA,Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA,Corresponding author: Sri-Rajasekhar Kothapalli, 325 CBE Building, State College, PA, 16802, USA,
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7
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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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8
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Yang C, Zhu J, Zhu L, Fan F, Ma Z, Zhang F. Rapid estimations of intensity standard deviations for optical coherence tomography angiography. JOURNAL OF BIOPHOTONICS 2022; 15:e202100340. [PMID: 34951745 DOI: 10.1002/jbio.202100340] [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: 11/04/2021] [Revised: 11/22/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
Optical coherence tomography angiography (OCTA) can map microvascular networks and quantify blood flow velocities with high resolution by calculating intensity standard deviations of time-series signals. However, statistical calculations of the standard deviations need much processing time and reduce the analysis efficiency. In this study, we proposed three optimized OCTA algorithms incorporating rapid estimations of the intensity standard deviations, including the range algorithm, the mean absolute error algorithm and the maximum absolute error algorithm. The abilities of the optimized algorithms to quantify the flow velocities were validated by a flow phantom. After a rat cerebral cortex was imaged, the optimized OCTA algorithms were compared with the conventional relative standard deviation algorithm in the metrics of imaging quality and processing time. The results show that the optimized algorithms incorporating rapid estimations of the intensity standard deviations have faster processing speeds with equivalent image quality.
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Affiliation(s)
- Chaojiang Yang
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Laboratory of Biomedical Testing Technology and Instruments, Beijing Information Science and Technology University, Beijing, China
| | - Jiang Zhu
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Laboratory of Biomedical Testing Technology and Instruments, Beijing Information Science and Technology University, Beijing, China
| | - Lianqing Zhu
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Key Laboratory of Optoelectronic Measurement Technology, Beijing Information Science and Technology University, Beijing, China
| | - Fan Fan
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Laboratory of Biomedical Testing Technology and Instruments, Beijing Information Science and Technology University, Beijing, China
| | - Zongqing Ma
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Laboratory of Biomedical Testing Technology and Instruments, Beijing Information Science and Technology University, Beijing, China
| | - Fan Zhang
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing, China
- Beijing Laboratory of Biomedical Testing Technology and Instruments, Beijing Information Science and Technology University, Beijing, China
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9
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Untracht GR, Matos RS, Dikaios N, Bapir M, Durrani AK, Butsabong T, Campagnolo P, Sampson DD, Heiss C, Sampson DM. OCTAVA: An open-source toolbox for quantitative analysis of optical coherence tomography angiography images. PLoS One 2021; 16:e0261052. [PMID: 34882760 PMCID: PMC8659314 DOI: 10.1371/journal.pone.0261052] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 11/24/2021] [Indexed: 12/15/2022] Open
Abstract
Optical coherence tomography angiography (OCTA) performs non-invasive visualization and characterization of microvasculature in research and clinical applications mainly in ophthalmology and dermatology. A wide variety of instruments, imaging protocols, processing methods and metrics have been used to describe the microvasculature, such that comparing different study outcomes is currently not feasible. With the goal of contributing to standardization of OCTA data analysis, we report a user-friendly, open-source toolbox, OCTAVA (OCTA Vascular Analyzer), to automate the pre-processing, segmentation, and quantitative analysis of en face OCTA maximum intensity projection images in a standardized workflow. We present each analysis step, including optimization of filtering and choice of segmentation algorithm, and definition of metrics. We perform quantitative analysis of OCTA images from different commercial and non-commercial instruments and samples and show OCTAVA can accurately and reproducibly determine metrics for characterization of microvasculature. Wide adoption could enable studies and aggregation of data on a scale sufficient to develop reliable microvascular biomarkers for early detection, and to guide treatment, of microvascular disease.
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Affiliation(s)
- Gavrielle R. Untracht
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia
- Surrey Biophotonics, Advanced Technology Institute, School of Physics and School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
- * E-mail:
| | - Rolando S. Matos
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | | | - Mariam Bapir
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Abdullah K. Durrani
- Surrey Biophotonics, Advanced Technology Institute, School of Physics and School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Teemapron Butsabong
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Paola Campagnolo
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - David D. Sampson
- Surrey Biophotonics, Advanced Technology Institute, School of Physics and School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Christian Heiss
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
- Surrey and Sussex Healthcare NHS Trust, East Surrey Hospital, Redhill, Surrey, United Kingdom
| | - Danuta M. Sampson
- Department of Biochemical Sciences and Department of Clinical and Experimental Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
- Surrey Biophotonics, Centre for Vision, Speech and Signal Processing and School of Biosciences and Medicine, The University of Surrey, Guildford, United Kingdom
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10
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Dadkhah A, Paudel D, Jiao S. Comparative study of optical coherence tomography angiography algorithms for rodent retinal imaging. Exp Biol Med (Maywood) 2021; 246:2207-2213. [PMID: 34120494 DOI: 10.1177/15353702211024572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Optical coherence tomography angiography (OCTA) is a functional extension of optical coherence tomography for non-invasive in vivo three-dimensional imaging of the microvasculature of biological tissues. Several algorithms have been developed to construct OCTA images from the measured optical coherence tomography signals. In this study, we compared the performance of three OCTA algorithms that are based on the variance of phase, amplitude, and the complex representations of the optical coherence tomography signals for rodent retinal imaging, namely the phase variance, improved speckle contrast, and optical microangiography. The performance of the different algorithms was evaluated by comparing the quality of the OCTA images regarding how well the vasculature network can be resolved. Quantities that are widely used in ophthalmic studies including blood vessel density, vessel diameter index, vessel perimeter index, vessel complexity index were also compared. Results showed that both the improved speckle contrast and optical microangiography algorithms are more robust than phase variance, and they can reveal similar vasculature features while there are statistical differences in the calculated quantities.
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Affiliation(s)
- Arash Dadkhah
- Department of Biomedical Engineering, 5450Florida International University, Miami, FL 33174, USA
| | - Dhruba Paudel
- Department of Biomedical Engineering, 5450Florida International University, Miami, FL 33174, USA
| | - Shuliang Jiao
- Department of Biomedical Engineering, 5450Florida International University, Miami, FL 33174, USA
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11
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Use of Intense Pulsed Light Versus Pulsed-Dye Laser in the Treatment of Truncal Telangiectasia. Dermatol Surg 2021; 47:862-863. [PMID: 32897943 DOI: 10.1097/dss.0000000000002751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Mekonnen BK, Hsieh TH, Tsai DF, Liaw SK, Yang FL, Huang SL. Generation of Augmented Capillary Network Optical Coherence Tomography Image Data of Human Skin for Deep Learning and Capillary Segmentation. Diagnostics (Basel) 2021; 11:685. [PMID: 33920273 PMCID: PMC8068996 DOI: 10.3390/diagnostics11040685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 03/27/2021] [Accepted: 04/01/2021] [Indexed: 01/16/2023] Open
Abstract
The segmentation of capillaries in human skin in full-field optical coherence tomography (FF-OCT) images plays a vital role in clinical applications. Recent advances in deep learning techniques have demonstrated a state-of-the-art level of accuracy for the task of automatic medical image segmentation. However, a gigantic amount of annotated data is required for the successful training of deep learning models, which demands a great deal of effort and is costly. To overcome this fundamental problem, an automatic simulation algorithm to generate OCT-like skin image data with augmented capillary networks (ACNs) in a three-dimensional volume (which we called the ACN data) is presented. This algorithm simultaneously acquires augmented FF-OCT and corresponding ground truth images of capillary structures, in which potential functions are introduced to conduct the capillary pathways, and the two-dimensional Gaussian function is utilized to mimic the brightness reflected by capillary blood flow seen in real OCT data. To assess the quality of the ACN data, a U-Net deep learning model was trained by the ACN data and then tested on real in vivo FF-OCT human skin images for capillary segmentation. With properly designed data binarization for predicted image frames, the testing result of real FF-OCT data with respect to the ground truth achieved high scores in performance metrics. This demonstrates that the proposed algorithm is capable of generating ACN data that can imitate real FF-OCT skin images of capillary networks for use in research and deep learning, and that the model for capillary segmentation could be of wide benefit in clinical and biomedical applications.
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Affiliation(s)
- Bitewulign Kassa Mekonnen
- Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Da’an Dist., Taipei City 10607, Taiwan; (B.K.M.); (S.-K.L.)
- Research Center for Applied Sciences, Academia Sinica, No. 128, Academia Rd., Sec. 2, Nankang, Taipei City 11529, Taiwan; (D.-F.T.); (F.-L.Y.)
| | - Tung-Han Hsieh
- Research Center for Applied Sciences, Academia Sinica, No. 128, Academia Rd., Sec. 2, Nankang, Taipei City 11529, Taiwan; (D.-F.T.); (F.-L.Y.)
| | - Dian-Fu Tsai
- Research Center for Applied Sciences, Academia Sinica, No. 128, Academia Rd., Sec. 2, Nankang, Taipei City 11529, Taiwan; (D.-F.T.); (F.-L.Y.)
| | - Shien-Kuei Liaw
- Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Da’an Dist., Taipei City 10607, Taiwan; (B.K.M.); (S.-K.L.)
| | - Fu-Liang Yang
- Research Center for Applied Sciences, Academia Sinica, No. 128, Academia Rd., Sec. 2, Nankang, Taipei City 11529, Taiwan; (D.-F.T.); (F.-L.Y.)
- Department of Electrical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Rd., Sec. 4, Da’an Dist., Taipei City 10607, Taiwan
| | - Sheng-Lung Huang
- Graduate Institute of Photonics and Optoelectronics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei City 10617, Taiwan;
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13
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Imaging Motion: A Comprehensive Review of Optical Coherence Tomography Angiography. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1310:343-365. [PMID: 33834441 DOI: 10.1007/978-981-33-6064-8_12] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Optical coherence tomography (OCT) is a three-dimensional (3-D) optical imaging technology that provides noninvasive, micrometer resolution images of structural interiors within biological samples with an approximately 1 ~ 2 mm penetration depth. Over the last decades, advances in OCT have revolutionized biomedical imaging by demonstrating a potential of optical biopsy in preclinical and clinical settings. Recently, functional OCT imaging has shown a promise as angiography to visualize cell-perfused vasculatures in the tissue bed in vivo without requiring any exogenous contrast agents. This new technology termed OCT angiography (OCTA) possesses a unique imaging capability of delineating tissue morphology and blood or lymphatic vessels down to capillaries at real-time acquisition rates. For the past 10 years since 2007, OCTA has been proven to be a useful tool to identify disorder or dysfunction in tissue microcirculation from both experimental animal studies and clinical studies in ophthalmology and dermatology. In this section, we overview about OCTA including a basic principle of OCTA explained with simple optical physics, and its scan protocols and post-processing algorithms for acquisition of angiography. Then, potential and challenge of OCTA for clinical settings are shown with outcomes of human studies.
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Lee J, Jang WH, Shim S, Kim B, Jang WS, Myung JK, Park S, Kim KH. Characterization of early-stage cutaneous radiation injury by using optical coherence tomography angiography. BIOMEDICAL OPTICS EXPRESS 2020; 11:2652-2664. [PMID: 32499950 PMCID: PMC7249837 DOI: 10.1364/boe.387400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/12/2020] [Accepted: 04/13/2020] [Indexed: 05/09/2023]
Abstract
Cutaneous radiation injury (CRI) is a skin injury caused by exposure to high dose ionizing radiation (IR). Diagnosis and treatment of CRI is difficult due to its initial clinically latent period and the following inflammatory bursts. Early detection of CRI before clinical symptoms will be helpful for effective treatment, and various optical methods have been applied with limitations. Here we show that optical coherence tomography angiography (OCTA) could detect changes in the skin during the latent period in CRI mouse models non-invasively. CRI was induced on the mouse hindlimb with exposure to various IR doses and the injured skin regions were imaged longitudinally by OCTA until the onset of clinical symptoms. OCTA detected several changes in the skin including the skin thickening, the dilation of large blood vessels, and the irregularity in vessel boundaries. Some of OCTA findings were confirmed by histology. The study results showed that OCTA could be used for early CRI detection.
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Affiliation(s)
- Jungbin Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk 37673, South Korea
| | - Won Hyuk Jang
- Divison of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk 37673, South Korea
| | - Sehwan Shim
- National Radiation Emergency Medical Centre, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
| | - Bumju Kim
- Divison of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk 37673, South Korea
| | - Won-Suk Jang
- Laboratory of Experimental Pathology, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
| | - Jae Kyung Myung
- National Radiation Emergency Medical Centre, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
- Laboratory of Experimental Pathology, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
- Department of Pathology, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
| | - Sunhoo Park
- National Radiation Emergency Medical Centre, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
- Laboratory of Experimental Pathology, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
- Department of Pathology, Korea Cancer Centre Hospital, Korea Institute of Radiological & Medical Sciences (KIRAMS), 75 Nowon-ro, Nowon-gu, Seoul 01812, South Korea
| | - Ki Hean Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk 37673, South Korea
- Divison of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk 37673, South Korea
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15
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Dadkhah A, Jiao S. Integrating photoacoustic microscopy, optical coherence tomography, OCT angiography, and fluorescence microscopy for multimodal imaging. Exp Biol Med (Maywood) 2020; 245:342-347. [PMID: 31914810 DOI: 10.1177/1535370219897584] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We have developed a multimodal imaging system, which integrated optical resolution photoacoustic microscopy, optical coherence tomography, optical coherence tomography angiography, and confocal fluorescence microscopy in one platform. The system is able to image complementary features of a biological sample by combining different contrast mechanisms. We achieved fast imaging and large field of view by combining optical scanning with mechanical scanning, similar to our previous publication. We have demonstrated the capability of the multimodal imaging system by imaging a mouse ear in vivo. Impact statement Photoacoustic microscopy-based multimodal imaging technology can provide high-resolution complementary information for biological tissues in vivo. It will potentially bring significant impact on the research and diagnosis of diseases by providing combined structural and functional information.
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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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16
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Gubarkova EV, Feldchtein FI, Zagaynova EV, Gamayunov SV, Sirotkina MA, Sedova ES, Kuznetsov SS, Moiseev AA, Matveev LA, Zaitsev VY, Karashtin DA, Gelikonov GV, Pires L, Vitkin A, Gladkova ND. Optical coherence angiography for pre-treatment assessment and treatment monitoring following photodynamic therapy: a basal cell carcinoma patient study. Sci Rep 2019; 9:18670. [PMID: 31822752 PMCID: PMC6904495 DOI: 10.1038/s41598-019-55215-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/26/2019] [Indexed: 01/10/2023] Open
Abstract
Microvascular networks of human basal cell carcinomas (BCC) and surrounding skin were assessed with optical coherence angiography (OCA) in conjunction with photodynamic therapy (PDT). OCA images were collected and analyzed in 31 lesions pre-treatment, and immediately/24 hours/3-12 months post-treatment. Pre-treatment OCA enabled differentiation between prevalent subtypes of BCC (nodular and superficial) and nodular-with-necrotic-core BCC subtypes with a diagnostic accuracy of 78%; this can facilitate more accurate biopsy reducing sampling error and better therapy regimen selection. Post-treatment OCA images at 24 hours were 98% predictive of eventual outcome. Additional findings highlight the importance of pre-treatment necrotic core, vascular metrics associated with hypertrophic scar formation, and early microvascular changes necessary in both tumorous and peri-tumorous regions to ensure treatment success.
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Affiliation(s)
- E V Gubarkova
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia.
| | - F I Feldchtein
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia
| | - E V Zagaynova
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia
| | - S V Gamayunov
- A. Tsyb Medical Radiological Research Center, Korolev Street 4, Obninsk, 249036, Kaluga region, Russia
| | - M A Sirotkina
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia
| | - E S Sedova
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia
| | - S S Kuznetsov
- N.A. Semashko Nizhny Novgorod Regional Clinical Hospital, Rodionova Street 190, 603093, Nizhny Novgorod, Russia
| | - A A Moiseev
- Institute of Applied Physics Russian Academy of Science, Ulyanova Street 46, 603950, Nizhny Novgorod, Russia
| | - L A Matveev
- Institute of Applied Physics Russian Academy of Science, Ulyanova Street 46, 603950, Nizhny Novgorod, Russia
| | - V Y Zaitsev
- Institute of Applied Physics Russian Academy of Science, Ulyanova Street 46, 603950, Nizhny Novgorod, Russia
| | - D A Karashtin
- Institute of Applied Physics Russian Academy of Science, Ulyanova Street 46, 603950, Nizhny Novgorod, Russia
| | - G V Gelikonov
- Institute of Applied Physics Russian Academy of Science, Ulyanova Street 46, 603950, Nizhny Novgorod, Russia
| | - L Pires
- University of Toronto and University Health Network, 610 University Ave., Toronto, Ontario, M5G 2M9, Canada
| | - A Vitkin
- University of Toronto and University Health Network, 610 University Ave., Toronto, Ontario, M5G 2M9, Canada
| | - N D Gladkova
- Privolzhsky Research Medical University, Minina Square 10/1, 603005, Nizhny Novgorod, Russia
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17
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Meiburger KM, Chen Z, Sinz C, Hoover E, Minneman M, Ensher J, Kittler H, Leitgeb RA, Drexler W, Liu M. Automatic skin lesion area determination of basal cell carcinoma using optical coherence tomography angiography and a skeletonization approach: Preliminary results. JOURNAL OF BIOPHOTONICS 2019; 12:e201900131. [PMID: 31100191 PMCID: PMC7065618 DOI: 10.1002/jbio.201900131] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/15/2019] [Accepted: 05/16/2019] [Indexed: 05/05/2023]
Abstract
Cutaneous blood flow plays a key role in numerous physiological and pathological processes and has significant potential to be used as a biomarker to diagnose skin diseases such as basal cell carcinoma (BCC). The determination of the lesion area and vascular parameters within it, such as vessel density, is essential for diagnosis, surgical treatment and follow-up procedures. Here, an automatic skin lesion area determination algorithm based on optical coherence tomography angiography (OCTA) images is presented for the first time. The blood vessels are segmented within the OCTA images and then skeletonized. Subsequently, the skeleton is searched over the volume and numerous quantitative vascular parameters are calculated. The vascular density is then used to segment the lesion area. The algorithm is tested on both nodular and superficial BCC, and comparing with dermatological and histological results, the proposed method provides an accurate, non-invasive, quantitative and automatic tool for BCC lesion area determination.
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Affiliation(s)
- Kristen M. Meiburger
- Biolab, Department of Electronics and TelecommunicationsPolitecnico di TorinoTorinoItaly
| | - Zhe Chen
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Christoph Sinz
- Department of DermatologyMedical University of ViennaViennaAustria
| | | | | | | | - Harald Kittler
- Department of DermatologyMedical University of ViennaViennaAustria
| | - Rainer A. Leitgeb
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Mengyang Liu
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
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18
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Lacey AM, Fey RM, Gayken JR, Endorf FW, Schmitz KR, Punjabi GV, Masters TC, Nygaard RM. Microangiography: An Alternative Tool for Assessing Severe Frostbite Injury. J Burn Care Res 2019; 40:566-569. [DOI: 10.1093/jbcr/irz112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Abstract
Assessment of frostbite injury typically relies on computed tomography, angiography, or nuclear medicine studies to detect perfusion deficits prior to thrombolytic therapy. The aim of this study was to evaluate the potential of a novel imaging method, microangiography, in the assessment of severe frostbite injury. Patients with severe frostbite were included if they received a post-thrombolytic Technetium 99 (Tc99) bone scan, a Tc99 bone scan without thrombolytic therapy, and/or post-thrombolytic microangiography (MA) study. We included all patients from the years 2006 to 2018 with severe frostbite injury who had received appropriate imaging for diagnosis: Tc99 scan alone (N = 82), microangiography alone (N = 22), and both Tc99 and microangiography (N = 26). The majority of patients received thrombolytic therapy (76.2%), and the average time to thrombolytics was 6.9 hours. Tc99 scans showed strong correlation with amputation level (r = .836, P < .001), and microangiography showed a slightly stronger positive correlation with amputation level (r = .870, P < .001). In the subset who received both Tc99 scan and microangiography (N = 26), we observed significant differences in the mean scores of perfusion deficit (z = 3.20, P < .001). In this subset, a moderate correlation was found between level of perfusion deficit on Tc99 bone scan and amputation level (r = .525, P = .006). A very strong positive correlation was found between the microangiography studies and the amputation level (r = .890, P < .001). These results demonstrate that microangiography is a reliable alternative method of assessing severe frostbite injury and predicting amputation level.
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19
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Liu M, Drexler W. Optical coherence tomography angiography and photoacoustic imaging in dermatology. Photochem Photobiol Sci 2019; 18:945-962. [PMID: 30735220 DOI: 10.1039/c8pp00471d] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Optical coherence tomography angiography (OCTA) is a relatively novel functional extension of the widely accepted ophthalmic imaging tool named optical coherence tomography (OCT). Since OCTA's debut in ophthalmology, researchers have also been trying to expand its translational application in dermatology. The ability of OCTA to resolve microvasculature has shown promising results in imaging skin diseases. Meanwhile, photoacoustic imaging (PAI), which uses laser pulse induced ultrasound waves as the signal, has been studied to differentiate human skin layers and to help in skin disease diagnosis. This perspective article gives a short review of OCTA and PAI in the field of photodermatology. After an introduction to the principles of OCTA and PAI, we describe the most updated results of skin disease imaging using these two optical imaging modalities. We also place emphasis on dual modality imaging combining OCTA and photoacoustic tomography (PAT) for dermatological applications. In the end, the challenges and prospects of these two imaging modalities in dermatology are discussed.
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Affiliation(s)
- Mengyang Liu
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria.
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20
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Manfredini M, Bettoli V, Sacripanti G, Farnetani F, Bigi L, Puviani M, Corazza M, Pellacani G. The evolution of healthy skin to acne lesions: a longitudinal,
in vivo
evaluation with reflectance confocal microscopy and optical coherence tomography. J Eur Acad Dermatol Venereol 2019; 33:1768-1774. [DOI: 10.1111/jdv.15641] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/03/2019] [Indexed: 11/26/2022]
Affiliation(s)
- M. Manfredini
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
- Dermatology Unit Nuovo Ospedale Civile di Sassuolo Sassuolo Italy
| | - V. Bettoli
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
| | - G. Sacripanti
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - F. Farnetani
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - L. Bigi
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - M. Puviani
- Dermatology Unit Nuovo Ospedale Civile di Sassuolo Sassuolo Italy
| | - M. Corazza
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
| | - G. Pellacani
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
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Abstract
Despite our understanding that the microvasculature plays a multifaceted role in the development and progression of various conditions, we know little about the extent of this involvement. A need exists for non-invasive, clinically meaningful imaging modalities capable of elucidating microvascular information to aid in our understanding of disease, and to aid in the diagnosis/monitoring of disease for more patient-specific care. In this review article, a number of imaging techniques are summarized that have been utilized to investigate the microvasculature of skin, along with their advantages, disadvantages and future perspectives in preclinical and clinical settings. These techniques include dermoscopy, capillaroscopy, Doppler sonography, laser Doppler flowmetry (LDF) and perfusion imaging, laser speckle contrast imaging (LSCI), optical coherence tomography (OCT), including its Doppler and dynamic variant and the more recently developed OCT angiography (OCTA), photoacoustic imaging, and spatial frequency domain imaging (SFDI). Attention is largely, but not exclusively, placed on optical imaging modalities that use intrinsic optical signals to contrast the microvasculature. We conclude that whilst each imaging modality has been successful in filling a particular niche, there is no one, all-encompassing modality without inherent flaws. Therefore, the future of cutaneous microvascular imaging may lie in utilizing a multi-modal approach that will counter the disadvantages of individual systems to synergistically augment our imaging capabilities.
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Affiliation(s)
- Anthony J Deegan
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle, WA 98195, United States of America
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22
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Redd MA, Zeinstra N, Qin W, Wei W, Martinson A, Wang Y, Wang RK, Murry CE, Zheng Y. Patterned human microvascular grafts enable rapid vascularization and increase perfusion in infarcted rat hearts. Nat Commun 2019; 10:584. [PMID: 30718840 PMCID: PMC6362250 DOI: 10.1038/s41467-019-08388-7] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/04/2019] [Indexed: 12/23/2022] Open
Abstract
Vascularization and efficient perfusion are long-standing challenges in cardiac tissue engineering. Here we report engineered perfusable microvascular constructs, wherein human embryonic stem cell-derived endothelial cells (hESC-ECs) are seeded both into patterned microchannels and the surrounding collagen matrix. In vitro, the hESC-ECs lining the luminal walls readily sprout and anastomose with de novo-formed endothelial tubes in the matrix under flow. When implanted on infarcted rat hearts, the perfusable microvessel grafts integrate with coronary vasculature to a greater degree than non-perfusable self-assembled constructs at 5 days post-implantation. Optical microangiography imaging reveal that perfusable grafts have 6-fold greater vascular density, 2.5-fold higher vascular velocities and >20-fold higher volumetric perfusion rates. Implantation of perfusable grafts containing additional hESC-derived cardiomyocytes show higher cardiomyocyte and vascular density. Thus, pre-patterned vascular networks enhance vascular remodeling and accelerate coronary perfusion, potentially supporting cardiac tissues after implantation. These findings should facilitate the next generation of cardiac tissue engineering design.
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Affiliation(s)
- Meredith A Redd
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, 98109, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Nicole Zeinstra
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, 98109, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Wan Qin
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA
| | - Wei Wei
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA
| | - Amy Martinson
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, 98109, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA
- Department of Pathology, University of Washington, Seattle, WA, 98109, USA
| | - Yuliang Wang
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA
- Paul G. Allen School of Computer Science & Engineering, University of Washington, Seattle, WA, 98109, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA
| | - Charles E Murry
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA.
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, 98109, USA.
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA.
- Department of Pathology, University of Washington, Seattle, WA, 98109, USA.
- Department of Medicine/Cardiology, University of Washington, Seattle, WA, 98109, USA.
| | - Ying Zheng
- Department of Bioengineering, University of Washington, Seattle, WA, 98109, USA.
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, 98109, USA.
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA.
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23
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Silver FH, Shah RG, Benedetto D, Dulur A, Kirn T. Virtual Biopsy and Physical Characterization of Tissues, Biofilms, Implants and Viscoelastic Liquids Using Vibrational Optical Coherence Tomography. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/wjm.2019.91001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Silver FH, Shah RG. Mechanical spectroscopy and imaging of skin components in vivo: Assignment of the observed moduli. Skin Res Technol 2018; 25:47-53. [DOI: 10.1111/srt.12594] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2018] [Indexed: 11/29/2022]
Affiliation(s)
- F. H. Silver
- Department of Pathology and Laboratory Medicine; Robert Wood Johnson Medical School, Rutgers; The State University of New Jersey; Piscataway NJ USA
- OptoVibronex, LLC.; Mt. Bethel PA USA
| | - R. G. Shah
- Graduate Program in Biomedical Engineering, Rutgers; The State University of New Jersey; Piscataway NJ USA
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25
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New insights into the origin of remote PPG signals in visible light and infrared. Sci Rep 2018; 8:8501. [PMID: 29855610 PMCID: PMC5981460 DOI: 10.1038/s41598-018-26068-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/03/2018] [Indexed: 12/22/2022] Open
Abstract
Remote photoplethysmography (PPG) is an optical measurement technique with established applications in vital signs monitoring. Recently, the consensual understanding of blood volume variations (BVVs) as the origin of PPG signals was challenged, raising validity concerns about the remote SpO2 methodology. Recognizing the imperative for new opto-physiological evidence, this investigation supports the volumetric hypothesis with living skin experiments and Monte Carlo simulations of remote PPG-amplitude in visible light (VIS) and infrared (IR). Multilayered models of the skin were developed to simulate the separate contributions from skin layers containing pulsatile arterioles to the PPG signal in the 450–1000 nm range. The simulated spectra were qualitatively compared with observations of the resting and compressed finger pad, and complemented with videocapillaroscopy. Our results indicate that remote PPG systems indeed probe arterial blood. Green wavelengths probe dermal arterioles while red-IR wavelengths also reach subcutaneous BVVs. Owing to stable penetration depths, the red-IR diagnostic window promotes the invariance of SpO2 measurements to skin non-homogeneities.
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26
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Braaf B, Donner S, Nam AS, Bouma BE, Vakoc BJ. Complex differential variance angiography with noise-bias correction for optical coherence tomography of the retina. BIOMEDICAL OPTICS EXPRESS 2018; 9:486-506. [PMID: 29552388 PMCID: PMC5854053 DOI: 10.1364/boe.9.000486] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/03/2018] [Accepted: 01/03/2018] [Indexed: 05/05/2023]
Abstract
Complex differential variance (CDV) provides phase-sensitive angiographic imaging for optical coherence tomography (OCT) with immunity to phase-instabilities of the imaging system and small-scale axial bulk motion. However, like all angiographic methods, measurement noise can result in erroneous indications of blood flow that confuse the interpretation of angiographic images. In this paper, a modified CDV algorithm that corrects for this noise-bias is presented. This is achieved by normalizing the CDV signal by analytically derived upper and lower limits. The noise-bias corrected CDV algorithm was implemented into an experimental 1 μm wavelength OCT system for retinal imaging that used an eye tracking scanner laser ophthalmoscope at 815 nm for compensation of lateral eye motions. The noise-bias correction improved the CDV imaging of the blood flow in tissue layers with a low signal-to-noise ratio and suppressed false indications of blood flow outside the tissue. In addition, the CDV signal normalization suppressed noise induced by galvanometer scanning errors and small-scale lateral motion. High quality cross-section and motion-corrected en face angiograms of the retina and choroid are presented.
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Affiliation(s)
- Boy Braaf
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom St., Boston, Massachusetts 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Sabine Donner
- Heidelberg Engineering GmbH, Max-Jarecki-Straße 8, 69115 Heidelberg, Germany
| | - Ahhyun S. Nam
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom St., Boston, Massachusetts 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, USA
| | - Brett E. Bouma
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom St., Boston, Massachusetts 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
| | - Benjamin J. Vakoc
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom St., Boston, Massachusetts 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
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27
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Baran U, Choi WJ, Li Y, Wang RK. Tail artifact removal in OCT angiography images of rodent cortex. JOURNAL OF BIOPHOTONICS 2017; 10:1421-1429. [PMID: 27600882 PMCID: PMC5340634 DOI: 10.1002/jbio.201600194] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 08/16/2016] [Accepted: 08/21/2016] [Indexed: 05/11/2023]
Abstract
Optical coherence tomography angiography (OCTA) is a surging non-invasive, label-free, in vivo volumetric imaging method, currently being translated to clinical ophthalmology and becoming popular in neuroscience. Despite its attractiveness, there is an inherent issue of using OCT angiograms for quantitative cerebrovascular studies: The dynamic scattering of moving erythrocytes within pial vasculature creates tail-like artifacts that shadow the capillary vessels in the deeper layers of cortex. This false flow effect is relatively benign for qualitative visualization purposes, but it might have a significant impact on quantitative interpretation of angiographic results. In this work, we propose a simple image processing method to remove these tail artifacts in depth-resolved OCTA images using an adaptive enface mask generated with OCT structural images. We demonstrate the effectiveness of our method by comparing vessel densities and vessel similarities of depth-resolved OCT angiograms in a stroke study in a rodent model, in vivo. Thanks to the ability of seeing through the tails of pial vessels, capillary vessels beneath these vessels could be recovered to some extend in the deeper layers of mouse cerebral cortex, leading to a more accurate quantification. Tail artifact removed enface OCT angiogram of deeper layer in vivo mouse cortex.
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Affiliation(s)
- Utku Baran
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Woo June Choi
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Yuandong Li
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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Manfredini M, Greco M, Farnetani F, Ciardo S, De Carvalho N, Mandel VD, Starace M, Pellacani G. Acne: morphologic and vascular study of lesions and surrounding skin by means of optical coherence tomography. J Eur Acad Dermatol Venereol 2017; 31:1541-1546. [PMID: 28556980 DOI: 10.1111/jdv.14369] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 04/28/2017] [Indexed: 11/29/2022]
Abstract
BACKGROUND Acne vulgaris is a disease of the pilosebaceous unit, characterized by hyper-keratinization process, comedos formation and inflammatory reactions. OBJECTIVE The definition of the morphology and the vascularization of acne lesions by means of dynamic optical coherence tomography (D-OCT), to non-invasively define the alterations occurring during the acne development and patient therapeutic management. METHODS A set of standardized clinical pictures and D-OCT images were acquired from 114 acne lesions of 31 volunteers, presenting mild to moderate acne and evaluated by experts. Fifteen patients treated with oral antibiotics were followed during time at 0, 20, 40, and 60 days. RESULTS Optical coherence tomography enabled to identify vascular and morphological aspects characterizing different types of acne lesions. Oral antibiotic treatment improved the morphologic features and decreased the digitally reconstructed vascular signal during time. CONCLUSION The characterization of acne lesions and the identification of vascular pattern in acne lesions through D-OCT, corresponding to blood vessel dilation and inflammatory associated hyper-vascularization, may have important clinical consequences in the assessment of acne severity, therapeutic decisions and treatment efficacy monitoring.
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Affiliation(s)
- M Manfredini
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - M Greco
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - F Farnetani
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - S Ciardo
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - N De Carvalho
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - V D Mandel
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - M Starace
- Division of Dermatology, Department of Specialized, Clinical, and Experimental Medicine, University of Bologna, Bologna, Italy
| | - G Pellacani
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
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Wei DW, Deegan AJ, Wang RK. Automatic motion correction for in vivo human skin optical coherence tomography angiography through combined rigid and nonrigid registration. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:066013. [PMID: 28636065 PMCID: PMC5478967 DOI: 10.1117/1.jbo.22.6.066013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
When using optical coherence tomography angiography (OCTA), the development of artifacts due to involuntary movements can severely compromise the visualization and subsequent quantitation of tissue microvasculatures. To correct such an occurrence, we propose a motion compensation method to eliminate artifacts from human skin OCTA by means of step-by-step rigid affine registration, rigid subpixel registration, and nonrigid B-spline registration. To accommodate this remedial process, OCTA is conducted using two matching all-depth volume scans. Affine transformation is first performed on the large vessels of the deep reticular dermis, and then the resulting affine parameters are applied to all-depth vasculatures with a further subpixel registration to refine the alignment between superficial smaller vessels. Finally, the coregistration of both volumes is carried out to result in the final artifact-free composite image via an algorithm based upon cubic B-spline free-form deformation. We demonstrate that the proposed method can provide a considerable improvement to the final en face OCTA images with substantial artifact removal. In addition, the correlation coefficients and peak signal-to-noise ratios of the corrected images are evaluated and compared with those of the original images, further validating the effectiveness of the proposed method. We expect that the proposed method can be useful in improving qualitative and quantitative assessment of the OCTA images of scanned tissue beds.
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Affiliation(s)
- David Wei Wei
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Anthony J. Deegan
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
- Address all correspondence to: Ruikang K. Wang, E-mail:
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30
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Baran U, Swanson E, Sanders JE, Wang RK. OCT-based microangiography for reactive hyperaemia assessment within residual limb skin of people with lower limb loss. Skin Res Technol 2017; 24:152-155. [PMID: 28544155 DOI: 10.1111/srt.12383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2017] [Indexed: 11/27/2022]
Affiliation(s)
- U Baran
- Department of Bioengineering, University of Washington, Seattle, WA, USA.,Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - E Swanson
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - J E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - R K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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31
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Men SJ, Chen CL, Wei W, Lai TY, Song SZ, Wang RK. Repeatability of vessel density measurement in human skin by OCT-based microangiography. Skin Res Technol 2017; 23:607-612. [PMID: 28514014 DOI: 10.1111/srt.12379] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2017] [Indexed: 12/26/2022]
Abstract
PURPOSE To investigate the repeatability of vessel density measurement at human arm skin in healthy subjects with OCT-based microangiography (OMAG). METHODS Four locations including volar wrist, volar forearm, shoulder, and volar upper arm were scanned using an optimized swept source OCT system, working at center wavelength of 1300 nm and A-line rate of 100 kHz. Three scans were acquired at each location at the same visit. Vascular images of papillary dermis, reticular dermis, and the whole dermis layer were generated with OMAG processing and automatic segmentation algorithms. The vessel density (VD) of each layer was calculated based on vascular images, and the repeatability of the VD at the same physiological location was thereafter assessed. RESULTS Fifteen healthy volunteers were included. High repeatability of VD was found for wrist, forearm, shoulder, and upper arm (coefficient of variation (CV)=2.4, 2.7, 2.7, 2.0, and intraclass correlation coefficient (ICC)=0.906, 0.854, 0.943, 0.916 respectively). The VD measurements showed no significant difference between the four locations in any of the three layers, ie papillary layer (P=.1063), reticular layer (P=.3371), and whole dermis layer (P=.3233). CONCLUSION Quantification of VD by using OCT/OMAG is repeatable when imaging skin tissue beds in healthy individuals.
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Affiliation(s)
- S J Men
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - C-L Chen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - W Wei
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - T-Y Lai
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - S Z Song
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - R K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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32
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Chen CL, Wang RK. Optical coherence tomography based angiography [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:1056-1082. [PMID: 28271003 PMCID: PMC5330554 DOI: 10.1364/boe.8.001056] [Citation(s) in RCA: 270] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/16/2017] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT)-based angiography (OCTA) provides in vivo, three-dimensional vascular information by the use of flowing red blood cells as intrinsic contrast agents, enabling the visualization of functional vessel networks within microcirculatory tissue beds non-invasively, without a need of dye injection. Because of these attributes, OCTA has been rapidly translated to clinical ophthalmology within a short period of time in the development. Various OCTA algorithms have been developed to detect the functional micro-vasculatures in vivo by utilizing different components of OCT signals, including phase-signal-based OCTA, intensity-signal-based OCTA and complex-signal-based OCTA. All these algorithms have shown, in one way or another, their clinical values in revealing micro-vasculatures in biological tissues in vivo, identifying abnormal vascular networks or vessel impairment zones in retinal and skin pathologies, detecting vessel patterns and angiogenesis in eyes with age-related macular degeneration and in skin and brain with tumors, and monitoring responses to hypoxia in the brain tissue. The purpose of this paper is to provide a technical oriented overview of the OCTA developments and their potential pre-clinical and clinical applications, and to shed some lights on its future perspectives. Because of its clinical translation to ophthalmology, this review intentionally places a slightly more weight on ophthalmic OCT angiography.
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Affiliation(s)
- Chieh-Li Chen
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA
- Department of Ophthalmology, University of Washington, 325 9th Ave, Seattle, WA 98104, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA
- Department of Ophthalmology, University of Washington, 325 9th Ave, Seattle, WA 98104, USA
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33
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Chen Z, Liu M, Minneman M, Ginner L, Hoover E, Sattmann H, Bonesi M, Drexler W, Leitgeb RA. Phase-stable swept source OCT angiography in human skin using an akinetic source. BIOMEDICAL OPTICS EXPRESS 2016; 7:3032-48. [PMID: 27570695 PMCID: PMC4986811 DOI: 10.1364/boe.7.003032] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 06/30/2016] [Accepted: 07/07/2016] [Indexed: 05/19/2023]
Abstract
We demonstrate noninvasive structural and microvascular contrast imaging of human skin in vivo, using phase difference swept source OCT angiography (pOCTA). The pOCTA system employs an akinetic, all-semiconductor, highly phase-stable swept laser source which operates at 1340 nm central wavelength, with 37 nm bandwidth (at 0 dB region) and 200 kHz A-scan rate. The phase sensitive detection does not need any external phase stabilizing implementations, due to the outstanding high phase linearity and sweep phase repeatability within 2 mrad. We compare the performance of phase based OCTA to speckle based OCTA for visualizing human vascular networks. pOCTA shows better contrast especially for deeper vascular details as compared to speckle based OCTA. The phase stability of the akinetic source allows the OCTA system to show decent vascular contrast only with 2 B-scans. We compare the performance of using 2 versus 4 B-scans for calculating the vascular contrast. Finally, the performance of a 100 nm bandwidth akinetic laser at 1310 nm is investigated for both OCT and OCTA.
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Affiliation(s)
- Zhe Chen
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Mengyang Liu
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Michael Minneman
- Insight Photonic Solutions, Inc., 300 S. Public Rd., Lafayette CO 80026, USA
| | - Laurin Ginner
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
- Christian Doppler Laboratory for Innovative Optical Imaging and its Translation to Medicine, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Erich Hoover
- Insight Photonic Solutions, Inc., 300 S. Public Rd., Lafayette CO 80026, USA
| | - Harald Sattmann
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
- Insight Photonic Solutions, Inc., 300 S. Public Rd., Lafayette CO 80026, USA
| | - Marco Bonesi
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Wolfgang Drexler
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Rainer A. Leitgeb
- Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
- Christian Doppler Laboratory for Innovative Optical Imaging and its Translation to Medicine, Währinger Gürtel 18-20, 1090 Vienna, Austria
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