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Han Y, Sun Y, Yang F, Liu Q, Fei W, Qiu W, Wang J, Li L, Zhang X, Wang A, Cui Y. Non-invasive imaging of pathological scars using a portable handheld two-photon microscope. Chin Med J (Engl) 2024; 137:329-337. [PMID: 37519215 PMCID: PMC10836882 DOI: 10.1097/cm9.0000000000002715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Indexed: 08/01/2023] Open
Abstract
BACKGROUND Pathological scars are a disorder that can lead to various cosmetic, psychological, and functional problems, and no effective assessment methods are currently available. Assessment and treatment of pathological scars are based on cutaneous manifestations. A two-photon microscope (TPM) with the potential for real-time non-invasive assessment may help determine the under-surface pathophysiological conditions in vivo . This study used a portable handheld TPM to image epidermal cells and dermal collagen structures in pathological scars and normal skin in vivo to evaluate the effectiveness of treatment in scar patients. METHODS Fifteen patients with pathological scars and three healthy controls were recruited. Imaging was performed using a portable handheld TPM. Five indexes were extracted from two dimensional (2D) and three dimensional (3D) perspectives, including collagen depth, dermo-epidermal junction (DEJ) contour ratio, thickness, orientation, and occupation (proportion of collagen fibers in the field of view) of collagen. Two depth-dependent indexes were computed through the 3D second harmonic generation image and three morphology-related indexes from the 2D images. We assessed index differences between scar and normal skin and changes before and after treatment. RESULTS Pathological scars and normal skin differed markedly regarding the epidermal morphological structure and the spectral characteristics of collagen fibers. Five indexes were employed to distinguish between normal skin and scar tissue. Statistically significant differences were found in average depth ( t = 9.917, P <0.001), thickness ( t = 4.037, P <0.001), occupation ( t = 2.169, P <0.050), orientation of collagen ( t = 3.669, P <0.001), and the DEJ contour ratio ( t = 5.105, P <0.001). CONCLUSIONS Use of portable handheld TPM can distinguish collagen from skin tissues; thus, it is more suitable for scar imaging than reflectance confocal microscopy. Thus, a TPM may be an auxiliary tool for scar treatment selection and assessing treatment efficacy.
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Affiliation(s)
- Yang Han
- Graduate School, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China
- Department of Dermatology, China-Japan Friendship Hospital, Beijing 100029, China
| | - Yuxuan Sun
- College of Engineering, Peking University, Beijing 100871, China
| | - Feili Yang
- School of Chemical Biology and Biotechnology, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
| | - Qingwu Liu
- Department of Dermatology, China-Japan Friendship Hospital, Beijing 100029, China
| | - Wenmin Fei
- Department of Dermatology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, China
| | - Wenzhuo Qiu
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Junjie Wang
- College of Future Technology, Peking University, Beijing 100871, China
| | - Linshuang Li
- Beijing Transcend Vivoscope Biotech, Beijing 100085, China
| | - Xuejun Zhang
- Department of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230001, China
- Institute of Dermatology, Anhui Medical University, Hefei, Anhui 230001, China
| | - Aimin Wang
- School of Electronics, Peking University, Beijing 100871, China
| | - Yong Cui
- Graduate School, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China
- Department of Dermatology, China-Japan Friendship Hospital, Beijing 100029, China
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2
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Ryu J, Kang D, Kim J, Chung A, Grant CN, Ryan E, Barrios A, Osman H, Tearney GJ. High-speed reflectance confocal microscopy of human skin at 1251-1342 nm. Lasers Surg Med 2023; 55:405-413. [PMID: 36924183 DOI: 10.1002/lsm.23652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/25/2023] [Accepted: 03/04/2023] [Indexed: 03/18/2023]
Abstract
OBJECTIVES Reflectance confocal microscopy (RCM) is an imaging method that can noninvasively visualize microscopic features of the human skin. The utility of RCM can be further improved by increasing imaging speed. In this paper, we report high-speed RCM imaging of human skin with a frame rate that is over 10 times faster and an area imaging rate that is 6-9 times faster than those of commercially available RCM devices. METHODS The higher imaging speed was achieved using a high-speed RCM technique, termed spectrally encoded confocal microscopy (SECM). SECM uses a diffraction grating and a high-speed, wavelength-swept source to conduct confocal imaging at a very high rate. We developed a handheld SECM probe using a scanned-grating approach. The SECM probe was used in conjunction with a wavelength-swept source with a spectral band of 1251-1342 nm. RESULTS The SECM probe achieved high lateral resolution of 1.3-1.6 µm and an axial resolution of 3.5 µm. SECM images of the human skin (image size = 439 × 439 µm2 ) obtained at 100 frames/s clearly show previously reported RCM features of the human skin in vivo with adequate image quality. The fast imaging speed allowed for the rapid acquisiton of volumetric SECM image data (200 frames covering a depth range of 200 µm) within 2 s. The use of 1251-1342 nm provided sufficient signal level and contrast required to visualize key cellular morphologic features. CONCLUSIONS These preliminary results demonstrate that high-speed SECM imaging of the human skin at 1251-1342 nm is feasible.
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Affiliation(s)
- Jiheun Ryu
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Dongkyun Kang
- Department of Biomedical Engineering, College of Optical Sciences, University of Arizona, Tucson, Arizona, USA
| | - Junyoung Kim
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Anita Chung
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Catriona N Grant
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Emily Ryan
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Amilcar Barrios
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Hany Osman
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Guillermo J Tearney
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA.,Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts, USA.,Harvard-MIT Division of Health Science and Technology, Cambridge, Massachusetts, USA
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3
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Park WY, Kim B, Chun JH, Hong SM, Oh BH, Kim KH. High-contrast visualization of human skin cancers with combined reflectance confocal and moxifloxacin-based two-photon microscopy: An ex vivo study. Lasers Surg Med 2022; 54:1226-1237. [PMID: 36087014 DOI: 10.1002/lsm.23600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 08/18/2022] [Accepted: 08/28/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND AND OBJECTIVES Precise determination of cancer margin during skin cancer surgery is crucial for complete resection and further clinical prognosis. Although reflection confocal microscopy (RCM) has been used for perioperative guiding, its reflection contrast has limitations in detecting cancer cells in the dermis. We previously developed combined reflection confocal (RC) and moxifloxacin-based two-photon (MB-TP) microscopy for sensitive cancer detection by using multiple contrast mechanisms. In this study, the performance of combined microscopy was characterized in various skin cancer specimens and compared with standard methods. MATERIALS AND METHODS Seven human skin specimens in total including two normal ones, three basal cell carcinomas (BCCs), and two squamous cell carcinomas (SCCs) were collected and imaged in fresh condition. Moxifloxacin ophthalmic solution was topically instilled for cell labeling for 3-5 minutes, then mosaic imaging with the combined microscopy was conducted. The imaged specimens were imaged again after exogenous nuclear labeling for comparison and then processed for standard hematoxylin and eosin histology. RESULTS Combined RC and MB-TP microscopy visualized both cell and extracellular matrix structures of the skin specimens with multiple contrasts of reflection, moxifloxacin fluorescence, autofluorescence, and second harmonic generation. It distinguished normal cell structures in the skin dermis such as hair follicles, sebaceous and eccrine glands from BCC nests, and SCCs based on cell organization. Normal cell structures had organized cell arrangements for their functions, while cancer cell structures had dense and disorganized cell arrangements. Cellular features found by combined microscopy images were confirmed by both TP microscopy with nuclear labeling and histological examination. CONCLUSIONS The imaging results showed the potential of combined microscopy for sensitive cancer detection and in vivo guiding of skin cancer surgery.
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Affiliation(s)
- Won Yeong Park
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, Republic of Korea
| | - Bumju Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk, Republic of Korea
| | - Ji Hyun Chun
- Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seung-Mo Hong
- Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Byung Ho Oh
- Department of Dermatology, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Ki Hean Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, Republic of Korea.,Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk, Republic of Korea
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4
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McAleer S, Fast A, Xue Y, Seiler MJ, Tang WC, Balu M, Baldi P, Browne AW. Deep Learning-Assisted Multiphoton Microscopy to Reduce Light Exposure and Expedite Imaging in Tissues With High and Low Light Sensitivity. Transl Vis Sci Technol 2021; 10:30. [PMID: 34668935 PMCID: PMC8543395 DOI: 10.1167/tvst.10.12.30] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Purpose Two-photon excitation fluorescence (2PEF) reveals information about tissue function. Concerns for phototoxicity demand lower light exposure during imaging. Reducing excitation light reduces the quality of the image by limiting fluorescence emission. We applied deep learning (DL) super-resolution techniques to images acquired from low light exposure to yield high-resolution images of retinal and skin tissues. Methods We analyzed two methods: a method based on U-Net and a patch-based regression method using paired images of skin (550) and retina (1200), each with low- and high-resolution paired images. The retina dataset was acquired at low and high laser powers from retinal organoids, and the skin dataset was obtained from averaging 7 to 15 frames or 70 frames. Mean squared error (MSE) and the structural similarity index measure (SSIM) were outcome measures for DL algorithm performance. Results For the skin dataset, the patches method achieved a lower MSE (3.768) compared with U-Net (4.032) and a high SSIM (0.824) compared with U-Net (0.783). For the retinal dataset, the patches method achieved an average MSE of 27,611 compared with 146,855 for the U-Net method and an average SSIM of 0.636 compared with 0.607 for the U-Net method. The patches method was slower (303 seconds) than the U-Net method (<1 second). Conclusions DL can reduce excitation light exposure in 2PEF imaging while preserving image quality metrics. Translational Relevance DL methods will aid in translating 2PEF imaging from benchtop systems to in vivo imaging of light-sensitive tissues such as the retina.
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Affiliation(s)
- Stephen McAleer
- Department of Computer Science, University of California, Irvine, Irvine, CA, USA.,Institute for Genomics and Bioinformatics, University of California, Irvine, Irvine, CA, USA
| | - Alexander Fast
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA, USA.,InfraDerm, LLC, Irvine, CA
| | - Yuntian Xue
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Magdalene J Seiler
- Department of Physical Medicine & Rehabilitation, University of California, Irvine, Irvine, CA, USA.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA, USA.,Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, Irvine, CA, USA
| | - William C Tang
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Mihaela Balu
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA, USA
| | - Pierre Baldi
- Department of Computer Science, University of California, Irvine, Irvine, CA, USA.,Institute for Genomics and Bioinformatics, University of California, Irvine, Irvine, CA, USA
| | - Andrew W Browne
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.,Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, Irvine, CA, USA.,Institute for Clinical and Translational Science, University of California, Irvine, Irvine, CA, USA
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5
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Wang K, Pan Y, Tong S, Chen X, Lu Y, Qiu P. Deep-skin multiphoton microscopy in vivo excited at 1600 nm: A comparative investigation with silicone oil and deuterium dioxide immersion. JOURNAL OF BIOPHOTONICS 2021; 14:e202100076. [PMID: 34160142 DOI: 10.1002/jbio.202100076] [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: 03/02/2021] [Revised: 05/17/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Multiphoton microscopy (MPM) excited at the 1700-nm window has enabled deep-tissue penetration in biological tissue, especially brain. MPM of skin may also benefit from this deep-penetration capability. Skin is a layered structure with varying refractive index (from 1.34 to 1.5). Consequently, proper immersion medium should be selected when imaging with high numerical aperture objective lens. To provide guidelines for immersion medium selection for skin MPM, here we demonstrate comparative experimental investigation of deep-skin MPM excited at 1600 nm in vivo, using both silicone oil and deuterium dioxide (D2 O) immersion. We specifically characterize imaging depths, signal levels and spatial resolution. Our results show that both immersion media give similar performance in imaging depth and spatial resolution, while signal levels are slightly better with silicone oil immersion. We also demonstrate that local injection of fluorescent beads into the skin is a viable technique for spatial resolution characterization in vivo.
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Affiliation(s)
- Ke Wang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Yi Pan
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Shen Tong
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Xinlin Chen
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Yuan Lu
- Department of Dermatology, The sixth Hospital of Shenzhen University (Nanshan Hospital), Shenzhen, China
| | - Ping Qiu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
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6
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Borah BJ, Lee JC, Chi HH, Hsiao YT, Yen CT, Sun CK. Nyquist-exceeding high voxel rate acquisition in mesoscopic multiphoton microscopy for full-field submicron resolution resolvability. iScience 2021; 24:103041. [PMID: 34585109 PMCID: PMC8450254 DOI: 10.1016/j.isci.2021.103041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/15/2021] [Accepted: 08/23/2021] [Indexed: 12/04/2022] Open
Abstract
The Nyquist-Shannon criterion has never been realized in a laser-scanning mesoscopic multiphoton microscope (MPM) with a large field-of-view (FOV)-resolution ratio, especially when employing a high-frequency resonant-raster-scanning. With a high optical resolution nature, a current mesoscopic-MPM either neglects the criterion and degrades the digital resolution to twice the pixel size, or reduces the FOV and/or the raster-scanning speed to avoid aliasing. We introduce a Nyquist figure-of-merit (NFOM) parameter to characterize a laser-scanning MPM in terms of its optical-resolution retrieving ability. Based on NFOM, we define the maximum aliasing-free FOV, and subsequently, a cross-over excitation wavelength, below which the FOV becomes NFOM-constrained irrespective of an optimized optical design. We validate our idea in a custom-built mesoscopic-MPM with millimeter-scale FOV yielding an ultra-high FOV-resolution ratio of >3,000, while securing up-to a 1.6 mm Nyquist-satisfied aliasing-free FOV, a ∼400 nm lateral resolution, and a 70 M/s effective voxel-sampling rate, all at the same time. Nyquist figure-of-merit is introduced to characterize laser-scanning MPM digitization Maximum aliasing-free FOV and cross-over excitation wavelength are formulated High repetition-rate laser can enable high-speed large-FOV high-resolution MPM imaging Up-to 1.6 mm-wide non-aliased FOV and ∼400 nm digital resolution at 8 kHz line-rate
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Affiliation(s)
- Bhaskar Jyoti Borah
- Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan
| | - Jye-Chang Lee
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Han-Hsiung Chi
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Yang-Ting Hsiao
- Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan
| | - Chen-Tung Yen
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Chi-Kuang Sun
- Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan.,Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei 10617, Taiwan.,Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan
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7
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Csuka EA, Ward SC, Ekelem C, Csuka DA, Ardigò M, Mesinkovska NA. Reflectance Confocal Microscopy, Optical Coherence Tomography, and Multiphoton Microscopy in Inflammatory Skin Disease Diagnosis. Lasers Surg Med 2021; 53:776-797. [PMID: 33527483 DOI: 10.1002/lsm.23386] [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] [Received: 01/21/2020] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND OBJECTIVES Technological advances in medicine have brought about many novel skin imaging devices. This review aims to evaluate the scientific evidence supporting the use of noninvasive optical imaging techniques to aid in the diagnosis and prognosis of inflammatory skin diseases. STUDY DESIGN/MATERIALS AND METHODS PubMed and Scopus were searched in September 2020 according to PRISMA guidelines for articles using reflectance confocal microscopy (RCM), optical coherence tomography (OCT), and multiphoton microscopy (MPM) in inflammatory skin diseases, excluding studies monitoring treatment efficacy. RESULTS At the time of the study, there were 66 articles that addressed the utilization of noninvasive imaging in interface, spongiotic, psoriasiform, vesiculobullous, and fibrosing/sclerosing inflammatory skin dermatoses: RCM was utilized in 46, OCT in 16, and MPM in 5 articles. RCM was most investigated in psoriasiform dermatoses, whereas OCT and MPM were both most investigated in spongiotic dermatoses, including atopic dermatitis and allergic contact dermatitis. CONCLUSIONS There is preliminary evidence to support the diagnostic potential of noninvasive optical imaging techniques in inflammatory skin diseases. Improvements in the devices and further correlation with histology will help broaden their utility. Additional studies are needed to determine the parameters for diagnostic features, disease differentiation, and staging of inflammatory skin conditions. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.
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Affiliation(s)
- Ella A Csuka
- Department of Dermatology, University of California, Irvine, Irvine, California, 92697
| | - Suzanne C Ward
- Department of Dermatology, University of California, Irvine, Irvine, California, 92697
| | - Chloe Ekelem
- Department of Dermatology, University of California, Irvine, Irvine, California, 92697
| | - David A Csuka
- Department of Dermatology, University of California, Irvine, Irvine, California, 92697
| | - Marco Ardigò
- San Gallicano Dermatological Institute-IRCCS, Via Chianesi 53, Rome, 00144, Italy
| | - Natasha A Mesinkovska
- Department of Dermatology, University of California, Irvine, Irvine, California, 92697
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8
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Fast A, Lal A, Durkin AF, Lentsch G, Harris RM, Zachary CB, Ganesan AK, Balu M. Fast, large area multiphoton exoscope (FLAME) for macroscopic imaging with microscopic resolution of human skin. Sci Rep 2020; 10:18093. [PMID: 33093610 PMCID: PMC7582965 DOI: 10.1038/s41598-020-75172-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/13/2020] [Indexed: 02/06/2023] Open
Abstract
We introduce a compact, fast large area multiphoton exoscope (FLAME) system with enhanced molecular contrast for macroscopic imaging of human skin with microscopic resolution. A versatile imaging platform, FLAME combines optical and mechanical scanning mechanisms with deep learning image restoration to produce depth-resolved images that encompass sub-mm2 to cm2 scale areas of tissue within minutes and provide means for a comprehensive analysis of live or resected thick human skin tissue. The FLAME imaging platform, which expands on a design recently introduced by our group, also features time-resolved single photon counting detection to uniquely allow fast discrimination and 3D virtual staining of melanin. We demonstrate its performance and utility by fast ex vivo and in vivo imaging of human skin. With the ability to provide rapid access to depth resolved images of skin over cm2 area and to generate 3D distribution maps of key sub-cellular skin components such as melanocytic dendrites and melanin, FLAME is ready to be translated into a clinical imaging tool for enhancing diagnosis accuracy, guiding therapy and understanding skin biology.
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Affiliation(s)
- Alexander Fast
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92612, USA
| | - Akarsh Lal
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92612, USA
| | - Amanda F Durkin
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92612, USA
| | - Griffin Lentsch
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92612, USA
| | - Ronald M Harris
- Department of Dermatology, University of California, Irvine, 1 Medical Plaza Dr., Irvine, CA, 92697, USA
| | - Christopher B Zachary
- Department of Dermatology, University of California, Irvine, 1 Medical Plaza Dr., Irvine, CA, 92697, USA
| | - Anand K Ganesan
- Department of Dermatology, University of California, Irvine, 1 Medical Plaza Dr., Irvine, CA, 92697, USA
| | - Mihaela Balu
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, 1002 Health Sciences Rd., Irvine, CA, 92612, USA.
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9
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Hu C, Field JJ, Kelkar V, Chiang B, Wernsing K, Toussaint KC, Bartels RA, Popescu G. Harmonic optical tomography of nonlinear structures. NATURE PHOTONICS 2020; 14:564-569. [PMID: 34367322 PMCID: PMC8341385 DOI: 10.1038/s41566-020-0638-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Second-harmonic generation microscopy is a valuable label-free modality for imaging non-centrosymmetric structures and has important biomedical applications from live-cell imaging to cancer diagnosis. Conventional second-harmonic generation microscopy measures intensity signals that originate from tightly focused laser beams, preventing researchers from solving the scattering inverse problem for second-order nonlinear materials. Here, we present harmonic optical tomography (HOT) as a novel modality for imaging microscopic, nonlinear and inhomogeneous objects. The HOT principle of operation relies on inter-ferometrically measuring the complex harmonic field and using a scattering inverse model to reconstruct the three-dimensional distribution of harmonophores. HOT enables strong axial sectioning via the momentum conservation of spatially and temporally broadband fields. We illustrate the HOT operation with experiments and reconstructions on a beta-barium borate crystal and various biological specimens. Although our results involve second-order nonlinear materials, we show that this approach applies to any coherent nonlinear process.
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Affiliation(s)
- Chenfei Hu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- These authors contributed equally: Chenfei Hu, Jeffrey J. Field
| | - Jeffrey J Field
- Microscope Imaging Network Core Facility, Colorado State University, Fort Collins, CO, USA
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, USA
- These authors contributed equally: Chenfei Hu, Jeffrey J. Field
| | - Varun Kelkar
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Benny Chiang
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Keith Wernsing
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, USA
| | | | - Randy A Bartels
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, USA
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Gabriel Popescu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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10
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Attia ABE, Bi R, Dev K, Du Y, Olivo M. Clinical noninvasive imaging and spectroscopic tools for dermatological applications: Review of recent progress. TRANSLATIONAL BIOPHOTONICS 2020. [DOI: 10.1002/tbio.202000010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Amalina Binte Ebrahim Attia
- Lab of Bio‐Optical Imaging, Singapore Bioimaging Consortium (SBIC) Agency for Science Technology and Research (A*STAR) Singapore Singapore
| | - Renzhe Bi
- Lab of Bio‐Optical Imaging, Singapore Bioimaging Consortium (SBIC) Agency for Science Technology and Research (A*STAR) Singapore Singapore
| | - Kapil Dev
- Lab of Bio‐Optical Imaging, Singapore Bioimaging Consortium (SBIC) Agency for Science Technology and Research (A*STAR) Singapore Singapore
| | | | - Malini Olivo
- Lab of Bio‐Optical Imaging, Singapore Bioimaging Consortium (SBIC) Agency for Science Technology and Research (A*STAR) Singapore Singapore
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11
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Lentsch G, Valdebran M, Saknite I, Smith J, Linden KG, König K, Barr RJ, Harris RM, Tromberg BJ, Ganesan AK, Zachary CB, Kelly KM, Balu M. Non-invasive optical biopsy by multiphoton microscopy identifies the live morphology of common melanocytic nevi. Pigment Cell Melanoma Res 2020; 33:869-877. [PMID: 32485062 PMCID: PMC7687135 DOI: 10.1111/pcmr.12902] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/24/2020] [Accepted: 05/21/2020] [Indexed: 11/30/2022]
Abstract
Multiphoton microscopy (MPM) is a promising non-invasive imaging tool for discriminating benign nevi from melanoma. In this study, we establish a MPM morphologic catalogue of common nevi, information that will be critical in devising strategies to distinguish them from nevi that are evolving to melanoma that may present with more subtle signs of malignancy. Thirty common melanocytic nevi were imaged in vivo using MPM. Quantitative parameters that can distinguish between different types of nevi were developed and confirmed by examining the histology of eleven of the imaged nevi. MPM features of nevi examined included cytologic morphology of melanocytes in the epidermis and dermis, the size and distribution of nevomelanocytes both within and around nests, the size of rete ridges, and the presence of immune cells in the dermis. Distinguishing features include cytological morphology, the size of nevomelanocytes, the size of nevomelanocyte nests, and the distribution of nevomelanocytes. Notably, these distinguishing characteristics were not easily appreciated in fixed tissues, highlighting essential differences in the morphology of live skin. Taken together, this work provides a morphologic compendium of normal nevi, information that will be critical in future studies directed at identifying melanocytic nevi that are evolving to melanoma.
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Affiliation(s)
- Griffin Lentsch
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, USA
| | - Manuel Valdebran
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Inga Saknite
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, USA
| | - Janellen Smith
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Kenneth G Linden
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Karsten König
- Department of Biophotonics and Laser Technology, Saarland University, Saarbrucken, Germany.,JenLab GmbH, Jena, Germany
| | - Ronald J Barr
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Ronald M Harris
- Department of Dermatology, University of California, Irvine, CA, USA
| | - Bruce J Tromberg
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, USA
| | - Anand K Ganesan
- Department of Dermatology, University of California, Irvine, CA, USA
| | | | - Kristen M Kelly
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, USA.,Department of Dermatology, University of California, Irvine, CA, USA
| | - Mihaela Balu
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA, USA
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12
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Kapsokalyvas D, van Zandvoort MAMJ. Molecular Imaging in Oncology: Advanced Microscopy Techniques. Recent Results Cancer Res 2020; 216:533-561. [PMID: 32594398 DOI: 10.1007/978-3-030-42618-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Preclinical studies usually require high levels of morphological, functional, and biochemical information at subcellular resolution. This type of information cannot be obtained from clinical imaging techniques, such as MRI, PET/CT, or US. Luckily, many microscopy techniques exist that can offer this information, also for malignant tissues and therapeutic approaches. In this overview, we discuss the various advanced optical microscopy techniques and their applications in oncological research. After a short introduction in Sect. 16.1, we continue in Sect. 16.2 with a discussion on fluorescent labelling strategies, followed in Sect. 16.3 by an in-depth description of confocal, light-sheet, two-photon, and super-resolution microscopy. We end in Sect. 16.4 with a focus on the applications, specifically in oncology.
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Affiliation(s)
- Dimitrios Kapsokalyvas
- School for Oncology and Developmental Biology GROW and School for Cardiovascular Diseases CARIM, Maastricht University, Maastricht, The Netherlands
- Institut für Molekulare Kreislaufforschung, Universitätsklinikum Aachen, Aachen, Germany
| | - Marc A M J van Zandvoort
- School for Oncology and Developmental Biology GROW and School for Cardiovascular Diseases CARIM, Maastricht University, Maastricht, The Netherlands.
- Institut für Molekulare Kreislaufforschung, Universitätsklinikum Aachen, Aachen, Germany.
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13
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Dadgar S, Rajaram N. Optical Imaging Approaches to Investigating Radiation Resistance. Front Oncol 2019; 9:1152. [PMID: 31750246 PMCID: PMC6848224 DOI: 10.3389/fonc.2019.01152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 10/16/2019] [Indexed: 12/14/2022] Open
Abstract
Radiation therapy is frequently the first line of treatment for over 50% of cancer patients. While great advances have been made in improving treatment response rates and reducing damage to normal tissue, radiation resistance remains a persistent clinical problem. While hypoxia or a lack of tumor oxygenation has long been considered a key factor in causing treatment failure, recent evidence points to metabolic reprogramming under well-oxygenated conditions as a potential route to promoting radiation resistance. In this review, we present recent studies from our lab and others that use high-resolution optical imaging as well as clinical translational optical spectroscopy to shine light on the biological basis of radiation resistance. Two-photon microscopy of endogenous cellular metabolism has identified key changes in both mitochondrial structure and function that are specific to radiation-resistant cells and help promote cell survival in response to radiation. Optical spectroscopic approaches, such as diffuse reflectance and Raman spectroscopy have demonstrated functional and molecular differences between radiation-resistant and sensitive tumors in response to radiation. These studies have uncovered key changes in metabolic pathways and present a viable route to clinical translation of optical technologies to determine radiation resistance at a very early stage in the clinic.
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Affiliation(s)
| | - Narasimhan Rajaram
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR, United States
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14
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Li J, Lin P, Tan Y, Cheng JX. Volumetric stimulated Raman scattering imaging of cleared tissues towards three-dimensional chemical histopathology. BIOMEDICAL OPTICS EXPRESS 2019; 10:4329-4339. [PMID: 31453014 PMCID: PMC6701556 DOI: 10.1364/boe.10.004329] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/12/2019] [Accepted: 07/22/2019] [Indexed: 05/18/2023]
Abstract
Thin tissue slice based histology has been used as a gold standard for disease diagnosis since over a hundred years ago. However, histopathological evaluation on two-dimensional slides suffers from large variations due to limited sampling. To improve the diagnostic accuracy, three-dimensional (3D) histology is performed through serial sectioning, staining, imaging and reconstruction of individual slices, which is highly time-consuming and labor intensive. We developed a volumetric stimulated Raman scattering (SRS) imaging method, which provides histology-like information in 3D context without the need for staining with dyes. Using a small molecule clearing agent, formamide, we performed tissue clearing within 30 min and achieved an imaging depth up to 500 µm in highly scattered tissues, including brain, kidney, liver and lung. Through a two-color SRS imaging scheme, we obtained histology-like images in cleared brain tissue slices. Our method has the potential for 3D tissue histopathology to improve the accuracy of histopathological examination.
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Affiliation(s)
- Junjie Li
- Department of Electrical and Computer Engineering, Boston University, 8 St. Mary’s St, Boston, MA 02215, USA
| | - Peng Lin
- Department of Electrical and Computer Engineering, Boston University, 8 St. Mary’s St, Boston, MA 02215, USA
| | - Yuying Tan
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Ji-Xin Cheng
- Department of Electrical and Computer Engineering, Boston University, 8 St. Mary’s St, Boston, MA 02215, USA
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215, USA
- Photonics Center, Boston University, 8 St. Mary’s St, Boston, MA 02215, USA
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15
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Chang H, Jang WH, Lee S, Kim B, Kim MJ, Kim WO, Ryoo YW, Oh BH, Kim KH. Moxifloxacin Labeling-Based Multiphoton Microscopy of Skin Cancers in Asians. Lasers Surg Med 2019; 52:373-382. [PMID: 31338864 DOI: 10.1002/lsm.23138] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/27/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND OBJECTIVES Although multiphoton microscopy (MPM) can visualize both cell and extracellular matrix (ECM) structures of the skin in high-contrast without exogenous labeling, label-free MPM is usually too slow to image clinically relevant large regions. A high-speed MPM method would be beneficial for evaluating clinical skin specimens by increasing the imaging area. In this study, moxifloxacin labeling-based MPM (moxifloxacin MPM) was characterized in various human skin cancer specimens. STUDY DESIGN/MATERIALS AND METHODS Moxifloxacin ophthalmic solution was used for cell-labeling and MPM imaging was conducted afterwards. Moxifloxacin MPM was characterized in ex vivo normal human skin and skin cancer specimens in comparison with the label-free MPM and fluorescence confocal microscopy (FCM) using acridine orange as a labeling agent. Then, moxifloxacin MPM was applied to various ex vivo human skin cancer specimens including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), dermatofibrosarcoma protuberans (DFSP). Results of moxifloxacin MPM were compared with bright-field clinical and histopathologic findings. RESULTS Moxifloxacin MPM imaged both cells and collagen in the skin, similarly to label-free MPM, but with enhanced fluorescence intensities in cells and enhanced imaging speeds. Moxifloxacin MPM imaged cells in the skin similarly to acridine orange-based FCM. Moxifloxacin MPM of various human skin cancer specimens imaged their specific cellular features. The microscopic features detected in moxifloxacin MPM were confirmed with histological images. CONCLUSIONS This observational pilot study demonstrated that moxifloxacin MPM could detect specific cellular features of various skin cancers in good correlation with histopathological images in Asian patients at the higher imaging speed than label-free MPM. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Hoonchul Chang
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Won Hyuk Jang
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Seunghun Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Bumju Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Myoung Joon Kim
- Department of Ophthalmology, Asan Medical Center, Asan University of Ulsan College of Medicine, 88 Olympic-ro, 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Won Oh Kim
- Department of Dermatology, Keimyung University School of Medicine, 1095 Dalgubeol-daero, Dalseo-gu, Daegu, 42601, Republic of Korea
| | - Young Wook Ryoo
- Department of Dermatology, Keimyung University School of Medicine, 1095 Dalgubeol-daero, Dalseo-gu, Daegu, 42601, Republic of Korea
| | - Byung Ho Oh
- Department of Dermatology, College of Medicine, Yonsei University, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Ki Hean Kim
- Division of Integrative Biosciences & Biotechnology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea.,Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
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16
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Sdobnov AY, Lademann J, Darvin ME, Tuchin VV. Methods for Optical Skin Clearing in Molecular Optical Imaging in Dermatology. BIOCHEMISTRY (MOSCOW) 2019; 84:S144-S158. [PMID: 31213200 DOI: 10.1134/s0006297919140098] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This short review describes recent progress in using optical clearing (OC) technique in skin studies. Optical clearing is an efficient tool for enhancing the probing depth and data quality in multiphoton microscopy and Raman spectroscopy. Here, we discuss the main mechanisms of OC, its safety, advantages, and limitations. The data on the OC effect on the skin water content are presented. It was demonstrated that 70% glycerol and 100% OmnipaqueTM 300 reduce the water content in the skin. Both OC agents (OCAs) significantly affect the strongly bound and weakly bound water. However, OmnipaqueTM 300 causes considerably less skin dehydration than glycerol. In addition, the results of examination of the OC effect on autofluorescence in two-photon excitation and background fluorescence in Raman scattering at different skin depths are presented. It is shown that OmnipaqueTM 300 is a promising OCA due to its ability to reduce background fluorescence in the upper skin layers. The possibility of multimodal imaging combining optical methods and OC technique is discussed.
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Affiliation(s)
- A Yu Sdobnov
- Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, 90570, Finland. .,Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, 410012, Russia
| | - J Lademann
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, 10117, Germany
| | - M E Darvin
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, 10117, Germany
| | - V V Tuchin
- Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, 410012, Russia.,Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control, Russian Academy of Sciences, Saratov, 410028, Russia.,Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, 634050, Russia.,Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia
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17
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Sdobnov AY, Darvin ME, Schleusener J, Lademann J, Tuchin VV. Hydrogen bound water profiles in the skin influenced by optical clearing molecular agents-Quantitative analysis using confocal Raman microscopy. JOURNAL OF BIOPHOTONICS 2019; 12:e201800283. [PMID: 30565427 DOI: 10.1002/jbio.201800283] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 12/14/2018] [Accepted: 12/17/2018] [Indexed: 05/21/2023]
Abstract
Confocal Raman microscopy has been used to measure depth-dependent profiles of porcine skin ex vivo in the high wavenumber region after application of molecular optical clearing agents (OCAs). Glycerol (70%) and iohexol (100% Omnipaque [300]) water solutions were used as OCAs and topically applied to porcine ear skin for 30 and 60 minutes. Using Gaussian function-based deconvolution, the changes of hydrogen bound water molecule types have been microscopically analyzed down to the depth of 200 μm. Results show that both OCAs induced skin dehydration (reduction of total water), which is 51.3% for glycerol (60 minutes), 33.1% for glycerol (30 minutes), 8.3% for Omnipaque (60 minutes) and 4.4% for Omnipaque (30 minutes), on average for the 40 to 200 μm depths. Among the water types in the skin, the following reduction was observed in concentration of weakly bound (51.1%, 33.2%, 7.5% and 4.6%), strongly bound (50.4%, 33.0%, 7.9% and 3.4%), tightly bound (63.6%, 42.3%, 26.1% and 12.9%) and unbound (55.4%, 28.7%, 10.1% and 5.9%) water types on average for the 40 to 200 μm depths, post application of glycerol (60 minutes), glycerol (30 minutes), Omnipaque (60 minutes) and Omnipaque (30 minutes), respectively. As most concentrated in the skin, weakly and strongly bound water types are preferentially involved in the OCA-induced water flux in the skin, and thus, are responsible for optical clearing efficiency.
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Affiliation(s)
- Anton Y Sdobnov
- Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, Finland
- Department of Optics and Biophotonics, Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, Russia
| | - Maxim E Darvin
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Johannes Schleusener
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Jürgen Lademann
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Valery V Tuchin
- Department of Optics and Biophotonics, Research-Educational Institute of Optics and Biophotonics, Saratov State University, Saratov, Russia
- Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control of RAS, Saratov, Russia
- Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia
- Laboratory of Molecular Imaging, Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
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18
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Functional imaging of visual cortical layers and subplate in awake mice with optimized three-photon microscopy. Nat Commun 2019; 10:177. [PMID: 30635577 PMCID: PMC6329792 DOI: 10.1038/s41467-018-08179-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 12/13/2018] [Indexed: 01/02/2023] Open
Abstract
Two-photon microscopy is used to image neuronal activity, but has severe limitations for studying deeper cortical layers. Here, we developed a custom three-photon microscope optimized to image a vertical column of the cerebral cortex > 1 mm in depth in awake mice with low (<20 mW) average laser power. Our measurements of physiological responses and tissue-damage thresholds define pulse parameters and safety limits for damage-free three-photon imaging. We image functional visual responses of neurons expressing GCaMP6s across all layers of the primary visual cortex (V1) and in the subplate. These recordings reveal diverse visual selectivity in deep layers: layer 5 neurons are more broadly tuned to visual stimuli, whereas mean orientation selectivity of layer 6 neurons is slightly sharper, compared to neurons in other layers. Subplate neurons, located in the white matter below cortical layer 6 and characterized here for the first time, show low visual responsivity and broad orientation selectivity. Two-photon microscopy is a powerful tool for studying neuronal activity but cannot easily image deeper cortical layers. Here, the authors design a custom microscope for three-photon microscopy and use it to reveal response properties of layer 5, 6, and subplate visual cortical neurons.
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19
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Lentsch G, Balu M, Williams J, Lee S, Harris RM, König K, Ganesan A, Tromberg BJ, Nair N, Santhanam U, Misra M. In vivo multiphoton microscopy of melasma. Pigment Cell Melanoma Res 2018; 32:403-411. [PMID: 30506627 DOI: 10.1111/pcmr.12756] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 10/05/2018] [Accepted: 10/21/2018] [Indexed: 11/29/2022]
Abstract
Melasma is a skin disorder characterized by hyperpigmented patches due to increased melanin production and deposition. In this pilot study, we evaluate the potential of multiphoton microscopy (MPM) to characterize non-invasively the melanin content, location, and distribution in melasma and assess the elastosis severity. We employed a clinical MPM tomograph to image in vivo morphological features in melasma lesions and adjacent normal skin in 12 patients. We imaged dermal melanophages in most dermal melasma lesions and occasionally in epidermal melasma. The melanin volume fraction values measured in epidermal melasma (14% ± 4%) were significantly higher (p < 0.05) than the values measured in perilesional skin (11% ± 3%). The basal keratinocytes of melasma and perilesions showed different melanin distribution. Elastosis was predominantly more severe in lesions than in perilesions and was associated with changes in melanin distribution of the basal keratinocytes. These results demonstrate that MPM may be a non-invasive imaging tool for characterizing melasma.
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Affiliation(s)
- Griffin Lentsch
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California, Irvine, California
| | - Mihaela Balu
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California, Irvine, California
| | - Joshua Williams
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California, Irvine, California
| | - Sanghoon Lee
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California, Irvine, California.,Department of Dermatology, Soonchunhyang University, Seoul, Korea
| | - Ronald M Harris
- Department of Dermatology, University of California, Irvine, California
| | - Karsten König
- Department of Biophotonics and Laser Technology, Saarland University, Saarbrucken, Germany
| | - Anand Ganesan
- Department of Dermatology, University of California, Irvine, California
| | - Bruce J Tromberg
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California, Irvine, California
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20
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Lentsch G, Balu M, Koenig K, Tromberg BJ, Zachary CB, Smith J. In vivo multiphoton microscopy of scabies. JAAD Case Rep 2018; 4:985-987. [PMID: 30417058 PMCID: PMC6218693 DOI: 10.1016/j.jdcr.2018.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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21
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Lin J, Saknite I, Valdebran M, Balu M, Lentsch G, Williams JN, Koenig K, Tromberg BJ, Atanaskova Mesinkovska N. Feature characterization of scarring and non-scarring types of alopecia by multiphoton microscopy. Lasers Surg Med 2018; 51:95-103. [PMID: 30248187 DOI: 10.1002/lsm.23017] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2018] [Indexed: 02/01/2023]
Abstract
OBJECTIVES Non-invasive visualization of hair follicles is important for proper diagnosis and management of alopecia; however, histological assessment remains the gold standard. Laser imaging technologies have made possible noninvasive in vivo evaluation of skin and hair follicle. The aim of this study was to evaluate the ability of multiphoton microscopy (MPM) to non-invasively identify morphological features that can distinguish scarring from non-scarring alopecia. METHODS MPM images were obtained from areas on the scalp affected by alopecia. Investigators blinded to the diagnosis analyzed hair follicle and shaft sizes. Patients were recruited and imaged at the UC Irvine Health Medical Center and the University of California, Irvine Beckman Laser Institute. Patients with androgenetic alopecia (AGA) and alopecia areata (AA), and scarring alopecia, in particular frontal fibrosing alopecia (FFA) were recruited and imaged from July 2016 to July 2017. RESULTS We imaged 5 normal scalp subjects and 12 patients affected by non-scarring (7 subjects) and scarring (5 subjects) alopecia. In normal and non-scarring alopecia patients, MPM identified presence of sebaceous glands associated with hair follicles. MPM images of scarring alopecia were characterized by the presence of inflammatory cells surrounding hair follicles. Measurements of hair follicle diameter sizes were found to be significantly smaller in scarring alopecia patients compared to normal (P < 0.001) and compared to non-scarring alopecia patients (P = 0.046); non-scarring hair follicles were also significantly smaller than normal hair follicles (P = 0.043). CONCLUSIONS This study shows that MPM imaging can non-invasively identify morphological features that distinguish scarring from non-scarring alopecia. Further studies are needed to validate this technique and evaluate its potential to be used as an aid for guiding treatment. Lasers Surg. Med. 51:95-103, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Jessica Lin
- Department of Dermatology, University of California, Irvine, California
| | - Inga Saknite
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Manuel Valdebran
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Mihaela Balu
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Griffin Lentsch
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Joshua N Williams
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Karsten Koenig
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Bruce J Tromberg
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
| | - Natasha Atanaskova Mesinkovska
- Department of Dermatology, University of California, Irvine, California
- Laser Microbeam and Medical Program, Beckman Laser Institute, Irvine, California
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22
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Lin P, Liu X, Wang S, Li X, Song Y, Li L, Cai S, Wang X, Chen J. Diagnosing pituitary adenoma in unstained sections based on multiphoton microscopy. Pituitary 2018; 21:362-370. [PMID: 29594837 DOI: 10.1007/s11102-018-0882-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE If we can find a new method that can achieve rapid diagnosis of adenoma during operation, it will help surgeon shorten the operation time and enhance the treatment efficacy. This study discusses the feasibility of multiphoton microscopy (MPM) in diagnosing pituitary adenoma. METHOD MPM, based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) is performed for the diagnosis of pituitary adenoma in unstained sections. RESULTS Our results show that MPM can reveal the variation of reticulin fiber by SHG signals of collagen, combined with the measurement of area of acinus, thickness of collagen fiber and collagen percentage. MPM can further reflect the change of meshwork in normal pituitary and hyperplasia quantitatively. And the characteristics of typical growth patterns of pituitary adenoma are demonstrated by the overlay of SHG and TPEF images. What's more, we can identify the boundary of normal pituitary, hyperplasia and adenoma from MPM images. And the experiment also results verify the feasibility of this method in frozen sections. CONCLUSION These results indicated that MPM can make a diagnosis of pituitary adenoma by the morphological changes without routine pathological processing including hematoxylin-eosin (H&E) staining and other special staining. Therefore, this technique is expected to help diagnosis of pituitary adenoma during operation.
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Affiliation(s)
- Peihua Lin
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou, 350007, People's Republic of China
| | - Xueyong Liu
- Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, People's Republic of China
| | - Shu Wang
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou, 350007, People's Republic of China
| | - Xiaoling Li
- Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, People's Republic of China
| | - Yankun Song
- Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, People's Republic of China
| | - Lianhuang Li
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou, 350007, People's Republic of China
| | - Shanshan Cai
- Department of Pathology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, 362000, People's Republic of China
| | - Xingfu Wang
- Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, People's Republic of China.
| | - Jianxin Chen
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory of Photonics Technology, Fujian Normal University, Fuzhou, 350007, People's Republic of China.
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Pinkert MA, Salkowski LR, Keely PJ, Hall TJ, Block WF, Eliceiri KW. Review of quantitative multiscale imaging of breast cancer. J Med Imaging (Bellingham) 2018; 5:010901. [PMID: 29392158 PMCID: PMC5777512 DOI: 10.1117/1.jmi.5.1.010901] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 12/19/2017] [Indexed: 12/12/2022] Open
Abstract
Breast cancer is the most common cancer among women worldwide and ranks second in terms of overall cancer deaths. One of the difficulties associated with treating breast cancer is that it is a heterogeneous disease with variations in benign and pathologic tissue composition, which contributes to disease development, progression, and treatment response. Many of these phenotypes are uncharacterized and their presence is difficult to detect, in part due to the sparsity of methods to correlate information between the cellular microscale and the whole-breast macroscale. Quantitative multiscale imaging of the breast is an emerging field concerned with the development of imaging technology that can characterize anatomic, functional, and molecular information across different resolutions and fields of view. It involves a diverse collection of imaging modalities, which touch large sections of the breast imaging research community. Prospective studies have shown promising results, but there are several challenges, ranging from basic physics and engineering to data processing and quantification, that must be met to bring the field to maturity. This paper presents some of the challenges that investigators face, reviews currently used multiscale imaging methods for preclinical imaging, and discusses the potential of these methods for clinical breast imaging.
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Affiliation(s)
- Michael A. Pinkert
- Morgridge Institute for Research, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Laboratory for Optical and Computational Instrumentation, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Medical Physics, Madison, Wisconsin, United States
| | - Lonie R. Salkowski
- University of Wisconsin–Madison, Department of Medical Physics, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Radiology, Madison, Wisconsin, United States
| | - Patricia J. Keely
- University of Wisconsin–Madison, Department of Cell and Regenerative Biology, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Biomedical Engineering, Madison, Wisconsin, United States
| | - Timothy J. Hall
- University of Wisconsin–Madison, Department of Medical Physics, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Biomedical Engineering, Madison, Wisconsin, United States
| | - Walter F. Block
- University of Wisconsin–Madison, Department of Medical Physics, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Radiology, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Biomedical Engineering, Madison, Wisconsin, United States
| | - Kevin W. Eliceiri
- Morgridge Institute for Research, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Laboratory for Optical and Computational Instrumentation, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Medical Physics, Madison, Wisconsin, United States
- University of Wisconsin–Madison, Department of Biomedical Engineering, Madison, Wisconsin, United States
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Quantification of Collagen Organization after Nerve Repair. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2017; 5:e1586. [PMID: 29632766 PMCID: PMC5889458 DOI: 10.1097/gox.0000000000001586] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 10/13/2017] [Indexed: 01/09/2023]
Abstract
Background: Clinical outcomes after nerve injury and repair remain suboptimal. Patients may be plagued by poor functional recovery and painful neuroma at the repair site, characterized by disorganized collagen and sprouting axons. Collagen deposition during wound healing can be intrinsically imaged using second harmonic generation (SHG) microscopy. The purpose of this study was to develop a protocol for SHG imaging of nerves and to assess whether collagen alignment can be quantified after nerve repair. Methods: Sciatic nerve transection and epineural repair was performed in male rats. The contralateral nerves were used as intra-animal controls. Ten-millimeter nerve segments were harvested and fixed onto slides. SHG images were collected using a 20× objective on a multiphoton microscope. Collagen fiber alignment was calculated using CurveAlign software. Alignment was calculated on a scale from 0 to 1, where 1 represents perfect alignment. Statistical analysis was performed using a linear mixed-effects model. Results: Eight male rats underwent right sciatic nerve repair using 9-0 Nylon suture. There were gross variations in collagen fiber organization in the repaired nerves compared with the controls. Quantitatively, collagen fibers were more aligned in the control nerves (mean alignment 0.754, SE 0.055) than in the repairs (mean alignment 0.413, SE 0.047; P < 0.001). Conclusions: SHG microscopy can be used to quantitate collagen after nerve repair via fiber alignment. Given that the development of neuroma likely reflects aberrant wound healing, ex vivo and/or in vivo SHG imaging may be useful for further investigation of the variables predisposing to neuroma.
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Mahou P, Malkinson G, Chaudan É, Gacoin T, Beaurepaire E, Supatto W. Metrology of Multiphoton Microscopes Using Second Harmonic Generation Nanoprobes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1701442. [PMID: 28926684 DOI: 10.1002/smll.201701442] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 08/09/2017] [Indexed: 05/22/2023]
Abstract
In multiphoton microscopy, the ongoing trend toward the use of excitation wavelengths spanning the entire near-infrared range calls for new standards in order to quantify and compare the performances of microscopes. This article describes a new method for characterizing the imaging properties of multiphoton microscopes over a broad range of excitation wavelengths in a straightforward and efficient manner. It demonstrates how second harmonic generation (SHG) nanoprobes can be used to map the spatial resolution, field curvature, and chromatic aberrations across the microscope field of view with a precision below the diffraction limit and with unique advantages over methods based on fluorescence. KTiOPO4 nanocrystals are used as SHG nanoprobes to measure and compare the performances over the 850-1100 nm wavelength range of several microscope objectives designed for multiphoton microscopy. Finally, this approach is extended to the post-acquisition correction of chromatic aberrations in multicolor multiphoton imaging. Overall, the use of SHG nanoprobes appears as a uniquely suited method to standardize the metrology of multiphoton microscopes.
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Affiliation(s)
- Pierre Mahou
- Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS, INSERM, Université Paris-Saclay, 91128, Palaiseau cedex, France
| | - Guy Malkinson
- Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS, INSERM, Université Paris-Saclay, 91128, Palaiseau cedex, France
| | - Élodie Chaudan
- Laboratory of Condensed Matter Physics, Ecole Polytechnique, CNRS, Université Paris-Saclay, 91128, Palaiseau cedex, France
| | - Thierry Gacoin
- Laboratory of Condensed Matter Physics, Ecole Polytechnique, CNRS, Université Paris-Saclay, 91128, Palaiseau cedex, France
| | - Emmanuel Beaurepaire
- Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS, INSERM, Université Paris-Saclay, 91128, Palaiseau cedex, France
| | - Willy Supatto
- Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS, INSERM, Université Paris-Saclay, 91128, Palaiseau cedex, France
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Balu M, Lentsch G, Korta DZ, König K, Kelly KM, Tromberg BJ, Zachary CB. In vivo multiphoton-microscopy of picosecond-laser-induced optical breakdown in human skin. Lasers Surg Med 2017; 49:555-562. [PMID: 28333369 PMCID: PMC5513776 DOI: 10.1002/lsm.22655] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2017] [Indexed: 01/06/2023]
Abstract
Importance Improvements in skin appearance resulting from treatment with fractionated picosecond‐lasers have been noted, but optimizing the treatment efficacy depends on a thorough understanding of the specific skin response. The development of non‐invasive laser imaging techniques in conjunction with laser therapy can potentially provide feedback for guidance and optimizing clinical outcome. Objective The purpose of this study was to demonstrate the capability of multiphoton microscopy (MPM), a high‐resolution, label‐free imaging technique, to characterize in vivo the skin response to a fractionated non‐ablative picosecond‐laser treatment. Design, Setting, and Participants Two areas on the arm of a volunteer were treated with a fractionated picosecond laser at the Dermatology Clinic, UC Irvine. The skin response to treatment was imaged in vivo with a clinical MPM‐based tomograph at 3 hours and 24 hours after treatment and seven additional time points over a 4‐week period. Main Outcomes and Measures MPM revealed micro‐injuries present in the epidermis. Pigmented cells were particularly damaged in the process, suggesting that melanin is likely the main absorber for laser induced optical breakdown. Results Damaged individual cells were distinguished as early as 3 hours post pico‐laser treatment with the 532 nm wavelength, and 24 hours post‐treatment with both 532 and 1064 nm wavelengths. At later time points, clusters of cellular necrotic debris were imaged across the treated epidermis. After 24 hours of treatment, inflammatory cells were imaged in the proximity of epidermal micro‐injuries. The epidermal injuries were exfoliated over a 4‐week period. Conclusions and Relevance This observational and descriptive pilot study demonstrates that in vivo MPM imaging can be used non‐invasively to provide label‐free contrast for describing changes in human skin following a fractionated non‐ablative laser treatment. The results presented in this study represent the groundwork for future longitudinal investigations on an expanded number of subjects to understand the response to treatment in different skin types with different laser parameters, critical factors in optimizing treatment outcome. Lasers Surg. Med. 49:555–562, 2017. © 2017 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Mihaela Balu
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California Irvine, Irvine, California, 92612
| | - Griffin Lentsch
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California Irvine, Irvine, California, 92612
| | - Dorota Z Korta
- Department of Dermatology, University of California, Irvine, California, 92697
| | - Karsten König
- JenLab GmbH, Schillerstrasse 1, Jena, Germany.,Department of Biophotonics and Laser Technology, Saarland University, Saarbrücken, Germany
| | - Kristen M Kelly
- Department of Dermatology, University of California, Irvine, California, 92697
| | - Bruce J Tromberg
- Beckman Laser Institute, Laser Microbeam and Medical Program, University of California Irvine, Irvine, California, 92612
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