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Zhang H, Kang DH, Piantino M, Tominaga D, Fujimura T, Nakatani N, Taylor JN, Furihata T, Matsusaki M, Fujita S. Rapid Quantification of Microvessels of Three-Dimensional Blood-Brain Barrier Model Using Optical Coherence Tomography and Deep Learning Algorithm. BIOSENSORS 2023; 13:818. [PMID: 37622905 PMCID: PMC10452445 DOI: 10.3390/bios13080818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/02/2023] [Accepted: 08/09/2023] [Indexed: 08/26/2023]
Abstract
The blood-brain barrier (BBB) is a selective barrier that controls the transport between the blood and neural tissue features and maintains brain homeostasis to protect the central nervous system (CNS). In vitro models can be useful to understand the role of the BBB in disease and assess the effects of drug delivery. Recently, we reported a 3D BBB model with perfusable microvasculature in a Transwell insert. It replicates several key features of the native BBB, as it showed size-selective permeability of different molecular weights of dextran, activity of the P-glycoprotein efflux pump, and functionality of receptor-mediated transcytosis (RMT), which is the most investigated pathway for the transportation of macromolecules through endothelial cells of the BBB. For quality control and permeability evaluation in commercial use, visualization and quantification of the 3D vascular lumen structures is absolutely crucial. Here, for the first time, we report a rapid, non-invasive optical coherence tomography (OCT)-based approach to quantify the microvessel network in the 3D in vitro BBB model. Briefly, we successfully obtained the 3D OCT images of the BBB model and further processed the images using three strategies: morphological imaging processing (MIP), random forest machine learning using the Trainable Weka Segmentation plugin (RF-TWS), and deep learning using pix2pix cGAN. The performance of these methods was evaluated by comparing their output images with manually selected ground truth images. It suggested that deep learning performed well on object identification of OCT images and its computation results of vessel counts and surface areas were close to the ground truth results. This study not only facilitates the permeability evaluation of the BBB model but also offers a rapid, non-invasive observational and quantitative approach for the increasing number of other 3D in vitro models.
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Affiliation(s)
- Huiting Zhang
- AIST-Osaka University Advanced Photonics and Biosensing Open Innovation Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (H.Z.); (J.N.T.); (M.M.)
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (D.-H.K.); (M.P.)
| | - Dong-Hee Kang
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (D.-H.K.); (M.P.)
| | - Marie Piantino
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (D.-H.K.); (M.P.)
| | - Daisuke Tominaga
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8565, Ibaraki, Japan;
| | - Takashi Fujimura
- SCREEN Holdings Co., Ltd., 322 Furukawa-cho, Hazukashi, Fushimi-ku, Kyoto 612-8486, Kyoto, Japan; (T.F.); (N.N.)
| | - Noriyuki Nakatani
- SCREEN Holdings Co., Ltd., 322 Furukawa-cho, Hazukashi, Fushimi-ku, Kyoto 612-8486, Kyoto, Japan; (T.F.); (N.N.)
| | - J. Nicholas Taylor
- AIST-Osaka University Advanced Photonics and Biosensing Open Innovation Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (H.Z.); (J.N.T.); (M.M.)
| | - Tomomi Furihata
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji 192-0392, Tokyo, Japan;
| | - Michiya Matsusaki
- AIST-Osaka University Advanced Photonics and Biosensing Open Innovation Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (H.Z.); (J.N.T.); (M.M.)
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (D.-H.K.); (M.P.)
| | - Satoshi Fujita
- AIST-Osaka University Advanced Photonics and Biosensing Open Innovation Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (H.Z.); (J.N.T.); (M.M.)
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (D.-H.K.); (M.P.)
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Fitzgerald S, Akhtar J, Schartner E, Ebendorff-Heidepriem H, Mahadevan-Jansen A, Li J. Multimodal Raman spectroscopy and optical coherence tomography for biomedical analysis. JOURNAL OF BIOPHOTONICS 2023; 16:e202200231. [PMID: 36308009 PMCID: PMC10082563 DOI: 10.1002/jbio.202200231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/19/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
Optical techniques hold great potential to detect and monitor disease states as they are a fast, non-invasive toolkit. Raman spectroscopy (RS) in particular is a powerful label-free method capable of quantifying the biomolecular content of tissues. Still, spontaneous Raman scattering lacks information about tissue morphology due to its inability to rapidly assess a large field of view. Optical Coherence Tomography (OCT) is an interferometric optical method capable of fast, depth-resolved imaging of tissue morphology, but lacks detailed molecular contrast. In many cases, pairing label-free techniques into multimodal systems allows for a more diverse field of applications. Integrating RS and OCT into a single instrument allows for both structural imaging and biochemical interrogation of tissues and therefore offers a more comprehensive means for clinical diagnosis. This review summarizes the efforts made to date toward combining spontaneous RS-OCT instrumentation for biomedical analysis, including insights into primary design considerations and data interpretation.
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Affiliation(s)
- Sean Fitzgerald
- Vanderbilt Biophotonics Center, Nashville, Tennessee, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Jobaida Akhtar
- School of Physical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, South Australia, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Adelaide, South Australia, Australia
| | - Erik Schartner
- School of Physical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, South Australia, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Adelaide, South Australia, Australia
| | - Heike Ebendorff-Heidepriem
- School of Physical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, South Australia, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Adelaide, South Australia, Australia
| | - Anita Mahadevan-Jansen
- Vanderbilt Biophotonics Center, Nashville, Tennessee, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Jiawen Li
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, South Australia, Australia
- Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, Adelaide, South Australia, Australia
- School of Electrical and Electronic Engineering, The University of Adelaide, Adelaide, South Australia, Australia
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3
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Fan YJ, Hsieh HY, Huang YR, Tsao C, Lee CM, Tahara H, Wu YC, Sheen HJ, Chen BC. Development of a water refractive index-matched microneedle integrated into a light sheet microscopy system for continuous embryonic cell imaging. LAB ON A CHIP 2022; 22:584-591. [PMID: 34951426 DOI: 10.1039/d1lc00827g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this study, microneedle-integrated light sheet microscopy (LSM) was developed for trapping and continuously imaging embryos of Caenorhabditis elegans with subcellular resolution. To reduce aberrations when the light sheet was propagated into the device, a microneedle was fabricated using a transparent, water refractive index-matched polymer. It was proven that when the light sheet emerged from the water-immersed objective and penetrated through the microneedle with a circular surface, even with a non-perpendicular incident angle, fewer aberrations were found. An embryo was injected into and trapped at the tip of the microneedle, which was positioned at the interrogation window of the LSM apparatus with the image plane perpendicular to the light sheet, and this setup was used to sequentially acquire embryo images. By applying the light sheet, higher-resolution, higher-contrast images were obtained. The system also showed low photobleaching and low phototoxicity to embryos of C. elegans. Furthermore, three-dimensional embryo images with a whole field of view of the microneedle could be achieved by stitching together images and reconstructing sequential two-dimensional embryo images.
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Affiliation(s)
- Yu-Jui Fan
- School of Biomedical Engineering, International PhD Program for Biomedical Engineering, International PhD Program for Cell Therapy and Regeneration Medicine, College of Medicine, Taipei Medical University, 250 Wuxing St., Taipei 11031, Taiwan.
| | - Han-Yun Hsieh
- School of Biomedical Engineering, International PhD Program for Biomedical Engineering, International PhD Program for Cell Therapy and Regeneration Medicine, College of Medicine, Taipei Medical University, 250 Wuxing St., Taipei 11031, Taiwan.
- Department of Cellular and Molecular Biology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8553, Japan
- Institute of Applied Mechanics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
| | - Yen-Ru Huang
- Institute of Applied Mechanics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
| | - Chieh Tsao
- Research Center for Applied Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan.
| | - Chia-Ming Lee
- Research Center for Applied Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan.
| | - Hidetoshi Tahara
- Department of Cellular and Molecular Biology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8553, Japan
| | - Yi-Chun Wu
- Institute of Molecular and Cellular Biology, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan
| | - Horn-Jiunn Sheen
- Institute of Applied Mechanics, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
| | - Bi-Chang Chen
- Research Center for Applied Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529, Taiwan.
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Sandiford L, Holmes AM, Mangion SE, Mohammed YH, Zvyagin AV, Roberts MS. Optical Characterization of Zinc Pyrithione. Photochem Photobiol 2019; 95:1142-1150. [DOI: 10.1111/php.13100] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 03/05/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Lydia Sandiford
- School of Pharmacy and Medical Sciences University of South Australia and Basil Hetzel Institute for Translational Health Research Adelaide SA Australia
| | - Amy M. Holmes
- School of Pharmacy and Medical Sciences University of South Australia and Basil Hetzel Institute for Translational Health Research Adelaide SA Australia
| | - Sean E. Mangion
- School of Pharmacy and Medical Sciences University of South Australia and Basil Hetzel Institute for Translational Health Research Adelaide SA Australia
| | - Yousuf H. Mohammed
- Therapeutics Research Centre Diamantina Institute Translational Research Institute University of Queensland Brisbane Qld Australia
| | - Andrei V. Zvyagin
- Department of Physics and Astronomy ARC Centre of Excellence for Nanoscale BioPhotonics Macquarie University Sydney NSW Australia
- Institute of Molecular Medicine Sechenov University Moscow Russia
| | - Michael S. Roberts
- School of Pharmacy and Medical Sciences University of South Australia and Basil Hetzel Institute for Translational Health Research Adelaide SA Australia
- Therapeutics Research Centre Diamantina Institute Translational Research Institute University of Queensland Brisbane Qld Australia
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Sindeeva OA, Gusliakova OI, Inozemtseva OA, Abdurashitov AS, Brodovskaya EP, Gai M, Tuchin VV, Gorin DA, Sukhorukov GB. Effect of a Controlled Release of Epinephrine Hydrochloride from PLGA Microchamber Array: In Vivo Studies. ACS APPLIED MATERIALS & INTERFACES 2018; 10:37855-37864. [PMID: 30299076 DOI: 10.1021/acsami.8b15109] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper presents the synthesis of highly biocompatible and biodegradable poly(lactide- co-glycolide) (PLGA) microchamber arrays sensitive to low-intensity therapeutic ultrasound (1 MHz, 1-2 W, 1 min). A reliable method was elaborated that allowed the microchambers to be uniformly filled with epinephrine hydrochloride (EH), with the possibility of varying the cargo amount. The maximum load of EH was 4.5 μg per array of 5 mm × 5 mm (about 24 pg of EH per single microchamber). A gradual, spontaneous drug release was observed to start on the first day, which is especially important in the treatment of acute patients. Ultrasound triggered a sudden substantial release of EH from the films. In vivo real-time studies using a laser speckle contrast imaging system demonstrated changes in the hemodynamic parameters as a consequence of EH release under ultrasound exposure. We recorded a decrease in blood flow as a vascular response to EH release from a PLGA microchamber array implanted subcutaneously in a mouse. This response was immediate and delayed (1 and 2 days after the implantation of the array). The PLGA microchamber array is a new, promising drug depot implantable system that is sensitive to external stimuli.
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Affiliation(s)
- Olga A Sindeeva
- School of Engineering and Materials Science , Queen Mary University of London , Mile End, Eng, 215 , London E1 4NS , United Kingdom
| | | | | | | | - Ekaterina P Brodovskaya
- School of Engineering and Materials Science , Queen Mary University of London , Mile End, Eng, 215 , London E1 4NS , United Kingdom
- Ogarev Mordovia State University , 68 Bolshevistskaya Street , Saransk 430005 , Russia
| | - Meiyu Gai
- School of Engineering and Materials Science , Queen Mary University of London , Mile End, Eng, 215 , London E1 4NS , United Kingdom
- Tomsk Polytechnic University , 30 Lenin Avenue , Tomsk 634050 , Russia
- Max Plank Institute of Polymer Research , 10 Ackermannweg , Mainz 55128 , Germany
| | - Valery V Tuchin
- Interdisciplinary Laboratory of Biophotonics , Tomsk State University , 36 Lenin Avenue , Tomsk 634050 , Russia
- Laboratory of Laser Diagnostics of Technical and Living Systems , Institute of Precision Mechanics and Control of RAS , 24 Rabochaya Street , 410028 Saratov , Russia
| | - Dmitry A Gorin
- Laboratory of Biophotonics, Center for Photonics and Quantum Materials , Skolkovo Institute of Science and Technology , Nobel Street, Building 3 , Moscow 121205 , Russia
| | - Gleb B Sukhorukov
- School of Engineering and Materials Science , Queen Mary University of London , Mile End, Eng, 215 , London E1 4NS , United Kingdom
- Tomsk Polytechnic University , 30 Lenin Avenue , Tomsk 634050 , Russia
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Chen KC, Arad A, Song ZM, Croaker D. High-definition neural visualization of rodent brain using micro-CT scanning and non-local-means processing. BMC Med Imaging 2018; 18:38. [PMID: 30376825 PMCID: PMC6208172 DOI: 10.1186/s12880-018-0280-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 10/15/2018] [Indexed: 01/12/2023] Open
Abstract
Background Micro-CT holds promising potential for phenotyping and histological purposes. However, few have clarified the difference in the neuroimaging quality between ex vivo and in vivo micro-CT scanners. In addition, no direct comparison has been made between micro-CT scans and standard microscopy. Furthermore, while the efficacy of various stains for yielding soft-tissue contrast in CT scans have been compared in other studies for embryos, staining protocols for larger samples have yet to be clarified. Lastly, post-acquisition processing for image enhancements have not been addressed. Methods Comparisons of postnatal rat brain micro-CT scans obtained through custom-built ex vivo and commercially available in vivo micro-CT scanners were made. Subsequently, the scanned rat brains were then H&E stained for microscopy. Neuroanatomy on micro-CT scanning and 4× microscopy of rat brain were compared. Diffusion and perfusion staining using iodine or PTA were trialled on adult and neonatal encapsulated rat brains. Different combinations of stain concentration and staining time were trialled. Post-acquisition denoising with NLM filter was completed using a modern General-Purpose Graphic Processing Unit (GPGPU) and custom code for prompt processing. Results Ex vivo micro-CT scans of iodine-stained postnatal rat brains yields 3D images with details comparable to 4× H&E light micrographs. Neural features shown on ex vivo micro-CT scans were significantly more distinctive than those on in vivo micro-CT scans. Both ex vivo and in vivo micro-CT scans required diffusion staining through small craniotomy. Perfusion staining is ineffective. Iodine staining was more efficient than PTA in terms of time. Consistently, enhancement made by NLM denoising on in vivo micro-CT images were more pronounced than that on ex vivo micro-CT scans due to their difference in image signal-to-noise indexes. Conclusions Micro-CT scanning is a powerful and versatile visualization tool available for qualitative and potential quantitative anatomical analysis. Simple diffusion staining via craniotomy with 1.5% iodine is an effective and minimal structural-invasive method for both in vivo and ex vivo micro-CT scanning for studying the microscopic morphology of neonatal and adult rat brains. Post-acquisition NLM filtering is an effective enhancement technique for in vivo micro-CT brain scans. Electronic supplementary material The online version of this article (10.1186/s12880-018-0280-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ko-Chin Chen
- The Canberra Hospital, Yamba Drive, Garran, ACT, 2605, Australia. .,Automated Analytics, Sugar Land, TX, 77479, USA. .,Medical School, Australian National University, Canberra, ACT, 2601, Australia.
| | - Alon Arad
- Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,Automated Analytics, Sugar Land, TX, 77479, USA
| | - Zan-Ming Song
- Medical School, Australian National University, Canberra, ACT, 2601, Australia
| | - David Croaker
- The Canberra Hospital, Yamba Drive, Garran, ACT, 2605, Australia.,Medical School, Australian National University, Canberra, ACT, 2601, Australia
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Sdobnov AY, Darvin ME, Genina EA, Bashkatov AN, Lademann J, Tuchin VV. Recent progress in tissue optical clearing for spectroscopic application. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 197:216-229. [PMID: 29433855 DOI: 10.1016/j.saa.2018.01.085] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/25/2018] [Accepted: 01/31/2018] [Indexed: 05/03/2023]
Abstract
This paper aims to review recent progress in optical clearing of the skin and over naturally turbid biological tissues and blood using this technique in vivo and in vitro with multiphoton microscopy, confocal Raman microscopy, confocal microscopy, NIR spectroscopy, optical coherence tomography, and laser speckle contrast imaging. Basic principles of the technique, its safety, advantages and limitations are discussed. The application of optical clearing agent on a tissue allows for controlling the optical properties of tissue. Optical clearing-induced reduction of tissue scattering significantly facilitates the observation of deep-located tissue regions, at the same time improving the resolution and image contrast for a variety of optical imaging methods suitable for clinical applications, such as diagnostics and laser treatment of skin diseases, mucosal tumor imaging, laser disruption of pathological abnormalities, etc.
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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 (National Research University of Russia), Astrakhanskaya 83, 410012 Saratov, Russian Federation.
| | - 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, Berlin Institute of Health, Charitéplatz 1, 10117 Berlin, Germany
| | - E A Genina
- Research-Educational Institute of Optics and Biophotonics, Saratov State University (National Research University of Russia), Astrakhanskaya 83, 410012 Saratov, Russian Federation; Interdisciplinary Laboratory of Biophotonics, Tomsk State University (National Research University of Russia), Lenin's av. 36, 634050 Tomsk, Russian Federation
| | - A N Bashkatov
- Research-Educational Institute of Optics and Biophotonics, Saratov State University (National Research University of Russia), Astrakhanskaya 83, 410012 Saratov, Russian Federation; Interdisciplinary Laboratory of Biophotonics, Tomsk State University (National Research University of Russia), Lenin's av. 36, 634050 Tomsk, Russian Federation
| | - 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, Berlin Institute of Health, Charitéplatz 1, 10117 Berlin, Germany
| | - V V Tuchin
- Research-Educational Institute of Optics and Biophotonics, Saratov State University (National Research University of Russia), Astrakhanskaya 83, 410012 Saratov, Russian Federation; Interdisciplinary Laboratory of Biophotonics, Tomsk State University (National Research University of Russia), Lenin's av. 36, 634050 Tomsk, Russian Federation; Laboratory of Laser Diagnostics of Technical and Living Systems, Institute of Precision Mechanics and Control RAS, Rabochaya 24, 410028 Saratov, Russian Federation
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Olsovsky C, Hinsdale T, Cuenca R, Cheng YSL, Wright JM, Rees TD, Jo JA, Maitland KC. Handheld tunable focus confocal microscope utilizing a double-clad fiber coupler for in vivo imaging of oral epithelium. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:56008. [PMID: 28541447 PMCID: PMC5444308 DOI: 10.1117/1.jbo.22.5.056008] [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: 12/16/2016] [Accepted: 05/08/2017] [Indexed: 05/08/2023]
Abstract
A reflectance confocal endomicroscope with double-clad fiber coupler and electrically tunable focus lens is applied to imaging of the oral mucosa. The instrument is designed to be lightweight and robust for clinical use. The tunable lens allows axial scanning through > 250 ?? ? m in the epithelium when the probe tip is placed in contact with tissue. Images are acquired at 6.6 frames per second with a field of view diameter up to 850 ?? ? m . In vivo imaging of a wide range of normal sites in the oral cavity demonstrates the accessibility of the handheld probe. In vivo imaging of clinical lesions diagnosed as inflammation and dysplasia illustrates the ability of reflectance confocal endomicroscopy to image cellular changes associated with pathology.
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Affiliation(s)
- Cory Olsovsky
- Texas A&M University, Biomedical Engineering Department, College Station, Texas, United States
| | - Taylor Hinsdale
- Texas A&M University, Biomedical Engineering Department, College Station, Texas, United States
| | - Rodrigo Cuenca
- Texas A&M University, Biomedical Engineering Department, College Station, Texas, United States
| | - Yi-Shing Lisa Cheng
- Texas A&M University College of Dentistry, Department of Diagnostic Sciences, Dallas, Texas, United States
| | - John M. Wright
- Texas A&M University College of Dentistry, Department of Diagnostic Sciences, Dallas, Texas, United States
| | - Terry D. Rees
- Texas A&M University College of Dentistry, Department of Periodontics, Dallas, Texas, United States
| | - Javier A. Jo
- Texas A&M University, Biomedical Engineering Department, College Station, Texas, United States
| | - Kristen C. Maitland
- Texas A&M University, Biomedical Engineering Department, College Station, Texas, United States
- Address all correspondence to: Kristen C. Maitland, E-mail:
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Abstract
Fibrous structures are an integral and dynamic feature of soft biological tissues that are directly related to the tissues' condition and function. A greater understanding of mechanical tissue behavior can be gained through quantitative analyses of structure alone, as well as its integration into computational models of soft tissue function. Histology and other nonoptical techniques have traditionally dominated the field of tissue imaging, but they are limited by their invasiveness, inability to provide resolution on the micrometer scale, and dynamic information. Recent advances in optical modalities can provide higher resolution, less invasive imaging capabilities, and more quantitative measurements. Here we describe contemporary optical imaging techniques with respect to their suitability in the imaging of tissue structure, with a focus on characterization and implementation into subsequent modeling efforts. We outline the applications and limitations of each modality and discuss the overall shortcomings and future directions for optical imaging of soft tissue structure.
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Affiliation(s)
- Will Goth
- Department of Biomedical Engineering
| | - John Lesicko
- Department of Biomedical Engineering
- Center for Cardiovascular Simulation, and
| | - Michael S Sacks
- Department of Biomedical Engineering
- Center for Cardiovascular Simulation, and
- Institute for Computational Engineering and Sciences, University of Texas, Austin, Texas 78712;
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Gong P, Es'haghian S, Harms KA, Murray A, Rea S, Kennedy BF, Wood FM, Sampson DD, McLaughlin RA. Optical coherence tomography for longitudinal monitoring of vasculature in scars treated with laser fractionation. JOURNAL OF BIOPHOTONICS 2016; 9:626-36. [PMID: 26260918 DOI: 10.1002/jbio.201500157] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 07/14/2015] [Accepted: 07/16/2015] [Indexed: 05/21/2023]
Abstract
This study presents the first in vivo longitudinal assessment of scar vasculature in ablative fractional laser treatment using optical coherence tomography (OCT). A method based on OCT speckle decorrelation was developed to visualize and quantify the scar vasculature over the treatment period. Through reliable co-location of the imaging field of view across multiple imaging sessions, and compensation for motion artifact, the study was able to track the same scar tissue over a period of several months, and quantify changes in the vasculature area density. The results show incidences of occlusion of individual vessels 3 days after the first treatment. The subsequent responses ˜20 weeks after the initial treatment show differences between immature and mature scars. Image analysis showed a distinct decrease (25 ± 13%, mean ± standard deviation) and increase (19 ± 5%) of vasculature area density for the immature and mature scars, respectively. This study establishes the feasibility of OCT imaging for quantitative longitudinal monitoring of vasculature in scar treatment. En face optical coherence tomography vasculature images pre-treatment (top) and ˜20 weeks after the first laser treatment (bottom) of a mature burn scar. Arrows mark the same vessel pattern.
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Affiliation(s)
- Peijun Gong
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia.
| | - Shaghayegh Es'haghian
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
| | - Karl-Anton Harms
- Burns Service of Western Australia, Royal Perth Hospital, Wellington Street, Perth WA, 6000, Australia
| | - Alexandra Murray
- Burns Service of Western Australia, Royal Perth Hospital, Wellington Street, Perth WA, 6000, Australia
| | - Suzanne Rea
- Burns Service of Western Australia, Royal Perth Hospital, Wellington Street, Perth WA, 6000, Australia
- Burn Injury Research Unit, School of Surgery, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
| | - Brendan F Kennedy
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
| | - Fiona M Wood
- Burns Service of Western Australia, Royal Perth Hospital, Wellington Street, Perth WA, 6000, Australia
- Burn Injury Research Unit, School of Surgery, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
| | - David D Sampson
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
- Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
| | - Robert A McLaughlin
- Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley WA, 6009, Australia
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Ben I, Layosh YY, Granot E. Study of a simple model for the transition between the ballistic and the diffusive regimes in diffusive media. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:66004. [PMID: 27271889 DOI: 10.1117/1.jbo.21.6.066004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 05/13/2016] [Indexed: 05/15/2023]
Abstract
A Monte Carlo simulation was utilized to investigate a simple model for the transition between the ballistic and the diffusive regimes in diffusive media. The simulation focuses on the propagation of visible and near-infrared light in biological tissues. This research has mainly two findings: (1) the transition can be described, as was found experimentally, with good accuracy by only two terms (ballistic and diffusive). (2) The model can be utilized for cases where the absorption coefficient is not negligible compared to the scattering coefficient by adding a power-law prefactor to the diffusive term.
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12
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Zhang F, Nance E, Alnasser Y, Kannan R, Kannan S. Microglial migration and interactions with dendrimer nanoparticles are altered in the presence of neuroinflammation. J Neuroinflammation 2016; 13:65. [PMID: 27004516 PMCID: PMC4802843 DOI: 10.1186/s12974-016-0529-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/13/2016] [Indexed: 12/11/2022] Open
Abstract
Background Microglial cells have been implicated in neuroinflammation-mediated injury in the brain, including neurodevelopmental disorders such as cerebral palsy (CP) and autism. Pro-inflammatory activation of microglial cells results in the impairment of their neuroprotective functions, leading to an exaggerated, ongoing immune dysregulation that can persist long after the initial insult. We have previously shown that dendrimer-mediated delivery of an anti-inflammatory agent can attenuate inflammation in a rabbit model of maternal inflammation-induced CP and significantly improve the motor phenotype, due to the ability of the dendrimer to selectively localize in activated microglia. Methods To elucidate the interactions between dendrimers and microglia, we created an organotypic whole-hemisphere brain slice culture model from newborn rabbits with and without exposure to inflammation in utero. We then used this model to analyze the dynamics of microglial migration and their interactions with dendrimers in the presence of neuroinflammation. Results Microglial cells in animals with CP had an amoeboid morphology and impaired cell migration, demonstrated by decreased migration distance and velocity when compared to cells in healthy, age-matched controls. However, this decreased migration was associated with a greater, more rapid dendrimer uptake compared to microglial cells from healthy controls. Conclusions This study demonstrates that maternal intrauterine inflammation is associated with impaired microglial function and movement in the newborn brain. This microglial impairment may play a role in the development of ongoing brain injury and CP in the offspring. Increased uptake of dendrimers by the “impaired” microglia can be exploited to deliver drugs specifically to these cells and modulate their functions. Host tissue and target cell characteristics are important aspects to be considered in the design and evaluation of targeted dendrimer-based nanotherapeutics for improved and sustained efficacy. This ex vivo model also provides a rapid screening tool for evaluation of the effects of various therapies on microglial function. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0529-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fan Zhang
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Elizabeth Nance
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA.,Present address: Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Yossef Alnasser
- Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Rangaramanujam Kannan
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.,Hugo Moser Research Center, Kennedy Krieger Institute, Baltimore, MD, 21205, USA
| | - Sujatha Kannan
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA. .,Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA. .,Hugo Moser Research Center, Kennedy Krieger Institute, Baltimore, MD, 21205, USA. .,Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA.
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13
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Gao W. Image contrast reduction mechanism in full-field optical coherence tomography. J Microsc 2016; 261:199-216. [PMID: 26892916 DOI: 10.1111/jmi.12333] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 09/15/2015] [Indexed: 11/28/2022]
Abstract
Correct interpretation of image contrast obtained with full-field optical coherence tomography (FFOCT) technique is required for accurate medical diagnosis applications. In this work, first, the characteristics of microscopic structures of tissue that generate the contrast in en-face tomographic image obtained with FFOCT are discussed. Then an overview is given of the parameters that affect image contrast. Finally, the contrast correction factor for correct image interpretation and the contrast limits to practical FFOCT systems are outlined.
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Affiliation(s)
- Wanrong Gao
- Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, P. R. China
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14
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15
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Charwat V, Schütze K, Holnthoner W, Lavrentieva A, Gangnus R, Hofbauer P, Hoffmann C, Angres B, Kasper C. Potential and limitations of microscopy and Raman spectroscopy for live-cell analysis of 3D cell cultures. J Biotechnol 2015; 205:70-81. [DOI: 10.1016/j.jbiotec.2015.02.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 01/26/2015] [Accepted: 02/02/2015] [Indexed: 02/07/2023]
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16
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McLaughlin RA, Noble PB, Sampson DD. Optical coherence tomography in respiratory science and medicine: from airways to alveoli. Physiology (Bethesda) 2015; 29:369-80. [PMID: 25180266 DOI: 10.1152/physiol.00002.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Optical coherence tomography is a rapidly maturing optical imaging technology, enabling study of the in vivo structure of lung tissue at a scale of tens of micrometers. It has been used to assess the layered structure of airway walls, quantify both airway lumen caliber and compliance, and image individual alveoli. This article provides an overview of the technology and reviews its capability to provide new insights into respiratory disease.
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Affiliation(s)
- Robert A McLaughlin
- Optical & Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Perth, Australia;
| | - Peter B Noble
- School of Anatomy, Physiology & Human Biology, and Centre for Neonatal Research & Education, School of Paediatrics and Child Health, The University of Western Australia, Crawley, Australia; and
| | - David D Sampson
- Optical & Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Perth, Australia; Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Perth, Australia
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17
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Zhao Q, Wei H, He Y, Ren Q, Zhou C. Evaluation of ultrasound and glucose synergy effect on the optical clearing and light penetration for human colon tissue using SD-OCT. JOURNAL OF BIOPHOTONICS 2014; 7:938-947. [PMID: 24458608 DOI: 10.1002/jbio.201300141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 11/18/2013] [Accepted: 12/02/2013] [Indexed: 06/03/2023]
Abstract
Topical application optical clearing agents (OCAs) can effectively enhance the tissue optical clearing on the human colon tissue, which has been demonstrated in our previous studies. Nevertheless, the strong light scattering still limits the diffusion rate of OCAs and penetration depth of light into the tissue. In this study, in order to further increase the diffusion of the OCA of glucose into tissue, we employ a method to improve the glucose permeability and light penetration with ultrasound (sonophoretic delivery, SP) and glucose (G) synergy on human normal and cancerous colon tissues in vitro, which was measured and quantified with spectral-domain optical coherence tomography (SD-OCT) technology. To evaluate the effect of ultrasound mediation, the percentages of OCT signal enhancement (PSE) and 1/e light-penetration depth were calculated for G alone and ultrasound-G treatments. The PSE was calculated at approximately 313 μm from the sample tissue surface. For normal and cancerous colon tissues the PSE were about 91.1 ± 10.6% and 65.3% ± 12.3% with 30% G/SP, but for the 30% G alone treatment it was about 78.6 ± 11.2% and 54.5% ± 9.3%, respectively. The max value of 1/e light-penetration depth for normal colon tissue was 0.47 ± 0.02 mm with 30% G alone and 0.60 ± 0.05 mm (p < 0.05)with 30% G/SP synergy. However, for the cancerous colon tissue the max value was 0.45 ± 0.01 mm and 0.57 ± 0.03 mm (p < 0.05), respectively. The obtained permeability coefficients showed a significant enhancement with ultrasound mediation. The mean permeability coefficients of 30% G/SP in normal and cancerous colon tissues were (6.3 ± 0.16) × 10(-6) cm/s and (12.1 ± 0.34) × 10(-6) cm/s (p < 0.05), respectively. These preliminary experiments showed that ultrasound can effectively enhance the tissue optical clearing and glucose diffusion rate as well as increase the light-penetration depth into biotissues.
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Affiliation(s)
- Qingliang Zhao
- School of Biomedical Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240, China
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18
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Contaldo M, Poh CF, Guillaud M, Lucchese A, Rullo R, Lam S, Serpico R, MacAulay CE, Lane PM. Oral mucosa optical biopsy by a novel handheld fluorescent confocal microscope specifically developed: technologic improvements and future prospects. Oral Surg Oral Med Oral Pathol Oral Radiol 2014; 116:752-8. [PMID: 24237726 DOI: 10.1016/j.oooo.2013.09.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 08/22/2013] [Accepted: 09/08/2013] [Indexed: 12/14/2022]
Abstract
OBJECTIVE This pilot study evaluated the baseline effectiveness of a novel handheld fluorescent confocal microscope (FCM) specifically developed for oral mucosa imaging and compared the results with the literature. STUDY DESIGN Four different oral sites (covering the mucosa of the lip and of the ventral tongue, the masticatory mucosa of the gingiva, and the specialized mucosa of the dorsal tongue) in 6 healthy nonsmokers were imaged by an FCM made up of a confocal fiberoptic probe ergonomically designed for in vivo oral examination, using light at the wavelength of 457 nm able to excite the fluorophore acriflavine hydrochloride, topically administered. In total, 24 mucosal areas were examined. RESULTS The FCM was able to distinctly define epithelial cells, bacterial plaque, and inflammatory cells and to image submucosal structures by detecting their intrinsic fluorescence. CONCLUSIONS When compared with other devices, this FCM allowed the user to image each oral site at higher magnification, thus resulting in a clearer view.
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Affiliation(s)
- Maria Contaldo
- Multidisciplinary Department of Medical-Surgical and Odontostomatological Specialties, Second University of Naples, Naples, Italy.
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19
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Matthews TE, Giacomelli MG, Brown WJ, Wax A. Fourier domain multispectral multiple scattering low coherence interferometry. APPLIED OPTICS 2013; 52:8220-8. [PMID: 24513821 DOI: 10.1364/ao.52.008220] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 10/15/2013] [Indexed: 05/22/2023]
Abstract
We have implemented multispectral multiple scattering low coherence interferometry (ms2/LCI) with Fourier domain data collection. The ms2/LCI system is designed to localize features with spectroscopic contrast with millimeter resolution up to 1 cm deep in scattering samples by using photons that have undergone multiple low-angle (forward) scattering events. Fourier domain detection both increases the data acquisition speed of the system and gives access to rich spectroscopic information, compared to the previous single channel, time-domain implementation. Separate delivery and detection angular apertures reduce collection of the diffuse background signal in order to isolate localized spectral features from deeper in scattering samples than would be possible with traditional spectroscopic optical coherence tomography. Light from a supercontinuum source is used to acquire absorption spectra of chromophores in the visible range within a tissue-like scattering phantom. An intensity modulation and digital lock-in detection scheme is implemented to mitigate relative intensity and spectral noise inherent in supercontinuum sources. The technical parameters of the system and comparative analysis are presented.
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20
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Olsovsky C, Shelton R, Carrasco-Zevallos O, Applegate BE, Maitland KC. Chromatic confocal microscopy for multi-depth imaging of epithelial tissue. BIOMEDICAL OPTICS EXPRESS 2013; 4:732-40. [PMID: 23667789 PMCID: PMC3646600 DOI: 10.1364/boe.4.000732] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 04/12/2013] [Accepted: 04/15/2013] [Indexed: 05/20/2023]
Abstract
We present a novel chromatic confocal microscope capable of volumetric reflectance imaging of microstructure in non-transparent tissue. Our design takes advantage of the chromatic aberration of aspheric lenses that are otherwise well corrected. Strong chromatic aberration, generated by multiple aspheres, longitudinally disperses supercontinuum light onto the sample. The backscattered light detected with a spectrometer is therefore wavelength encoded and each spectrum corresponds to a line image. This approach obviates the need for traditional axial mechanical scanning techniques that are difficult to implement for endoscopy and susceptible to motion artifact. A wavelength range of 590-775 nm yielded a >150 µm imaging depth with ~3 µm axial resolution. The system was further demonstrated by capturing volumetric images of buccal mucosa. We believe these represent the first microstructural images in non-transparent biological tissue using chromatic confocal microscopy that exhibit long imaging depth while maintaining acceptable resolution for resolving cell morphology. Miniaturization of this optical system could bring enhanced speed and accuracy to endomicroscopic in vivo volumetric imaging of epithelial tissue.
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21
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Glazowski CE, Zavislan J. A coherent model for turbid imaging with confocal microscopy. BIOMEDICAL OPTICS EXPRESS 2013; 4:500-13. [PMID: 23577285 PMCID: PMC3617712 DOI: 10.1364/boe.4.000500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 02/19/2013] [Accepted: 02/22/2013] [Indexed: 05/25/2023]
Abstract
We present an engineering model of coherent imaging within a turbid volume, such as human tissues, with a confocal microscope. The model is built to analyze the statistical effect of aberrations and multiply scattered light on the resulting image. Numerical modeling of theory is compared with experimental results. We describe the construction of a stable phantom that represents the statistical effect of object turbidity on the image recorded. The model and phantom can serve as basis for system optimization in turbid imaging.
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22
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Muldoon TJ, Burgess SA, Chen BR, Ratner D, Hillman EMC. Analysis of skin lesions using laminar optical tomography. BIOMEDICAL OPTICS EXPRESS 2012; 3:1701-12. [PMID: 22808439 PMCID: PMC3395492 DOI: 10.1364/boe.3.001701] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 06/19/2012] [Accepted: 06/19/2012] [Indexed: 05/03/2023]
Abstract
Evaluation of suspicious skin lesions by dermatologists is usually accomplished using white light examination and direct punch or surgical biopsy. However, these techniques can be imprecise for estimating a lesion's margin or level of dermal invasion when planning surgical resection. Laminar optical tomography (LOT) is an imaging technique capable of acquiring depth-sensitive information within scattering tissues. Here, we explore whether LOT data can be used to predict the depth and thickness of pigmented lesions using a range of simulations and phantom models. We then compare these results to LOT data acquired on normal and malignant skin lesions in vivo.
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Affiliation(s)
- Timothy J. Muldoon
- Laboratory for Functional Optical Imaging, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
- Equal contribution from both authors
| | - Sean A. Burgess
- Laboratory for Functional Optical Imaging, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
- Equal contribution from both authors
| | - Brenda R. Chen
- Laboratory for Functional Optical Imaging, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Désirée Ratner
- Department of Dermatology, Columbia University Medical Center, New York, NY 10027, USA
| | - Elizabeth M. C. Hillman
- Laboratory for Functional Optical Imaging, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
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23
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Abstract
In this article, we discuss the optical immersion method based on refractive index matching of scatterers (e.g., collagen, elastin fibers, cells and cell compartments) and the ground material (interstitial fluid and/or cytoplasm) of tissue and blood under the action of exogenous optical clearing agents. We analyze the optical clearing of fibrous and cell-structured tissues and blood from the point of view of receiving more valuable, normally hidden, information from spectroscopic and polarization measurements, confocal microscopy, optical coherence and optical projection tomography, as well as from nonlinear spectroscopies, such as two-photon fluorescence and second-harmonic generation techniques. Some important applications of the immersion technique to glucose sensing, drug delivery monitoring, improvements of image contrast and imaging depth, nondistortive delivery of laser radiation and precision tissue laser photodisruption, among others, are also described.
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Affiliation(s)
- Elina A Genina
- Research-Educational Institute of Optics and Biophotonics, Saratov State University, 410012 Saratov, Russia
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24
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Zhou Y, Wu X, Wang T, Ming T, Wang PN, Zhou LW, Chen JY. A comparison study of detecting gold nanorods in living cells with confocal reflectance microscopy and two-photon fluorescence microscopy. J Microsc 2010; 237:200-7. [PMID: 20096050 DOI: 10.1111/j.1365-2818.2009.03324.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two-photon fluorescence microscopy and confocal reflectance microscopy were compared to detect intracellular gold nanorods in rat basophilic leukaemia cells. The two-photon photoluminescence images of gold nanorods were acquired by an 800 nm fs laser with the power of milliwatts. The advantages of the obtained two-photon photoluminescence images are high spatial resolution and reduced background. However, a remarkable photothermal effect on cells was seen after 30 times continuous scanning of the femto-second laser, potentially affecting the subcellular localization pattern of the nanorods. In the case of confocal reflectance microscopy the images of gold nanorods can be obtained with the power of light source as low as microwatts, thus avoiding the photothermal effect, but the resolution of such images is reduced. We have noted that confocal reflectance images of cellular gold nanorods achieved with 50 microW 800 nm fs have a relatively poor resolution, whereas the 50 microW 488 nm CW laser can acquire reasonably satisfactory 3D reflectance images with improved resolution because of its shorter wavelength. Therefore, confocal reflectance microscopy may also be a suitable means to image intracellular gold nanorods with the advantage of reduced photothermal effect.
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Affiliation(s)
- Y Zhou
- Surface Physics Laboratory (National key laboratory), Department of Physics, Fudan University, Shanghai, China
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25
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Abstract
Three-dimensional (3D) cell cultures are important tools in cell biology research and tissue engineering because they more closely resemble the architectural microenvironment of natural tissue, compared to standard two-dimensional cultures. Microscopy techniques that function well for thin, optically transparent cultures, however, are poorly suited for imaging 3D cell cultures. Three-dimensional cultures may be thick and highly scattering, preventing light from penetrating without significant distortion. Techniques that can image thicker biological specimens at high resolution include confocal microscopy, multiphoton microscopy, and optical coherence tomography. In this chapter, these three imaging modalities are described and demonstrated in the assessment of functional and structural features of 3D chitosin scaffolds, 3D micro-topographic substrates from poly-dimethyl siloxane molds, and 3D Matrigel cultures. Using these techniques, dynamic changes to cells in 3D microenvironments can be non-destructively assessed repeatedly over time.
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Affiliation(s)
- Benedikt W Graf
- Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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LaCroix JT, Haidekker MA. Quantifying light scattering with single-mode fiber -optic confocal microscopy. BMC Med Imaging 2009; 9:19. [PMID: 19925674 PMCID: PMC2793246 DOI: 10.1186/1471-2342-9-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 11/19/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Confocal microscopy has become an important option for examining tissues in vivo as a diagnostic tool and a quality control tool for tissue-engineered constructs. Collagen is one of the primary determinants of biomechanical stability. Since collagen is also the primary scattering element in skin and other soft tissues, we hypothesized that laser-optical imaging methods, particularly confocal scattered-light scanning, would allow us to quantify scattering intensity and determine collagen content in biological layers. METHODS We built a fully automated confocal scattered-light scanner to examine how light scatters in Intralipid, a common tissue phantom, and three-dimensional collagen gels. Intralipid with 0.5%, 1.0%, 1.5%, and 2.0% concentration was filled between precisely spaced glass coverslips. Collagen gels at collagen concentrations from 0.30 mg/mL to 3.30 mg/mL were prepared, and all samples underwent A-mode scanning with multiple averaged scans. In Intralipid samples, light reflected from the upper fluid-glass interface was measured. In collagen gels, average scattering intensity inside the actual gel was measured. In both cases, intensity was correlated with concentration. RESULTS By measuring light attenuation at interface reflections of various thicknesses using our device, we were able to determine that the scattering coefficient at 660 nm of Intralipid at increasing concentrations in water to be 39 cm-1 for each percent increase of Intralipid. We were also able to measure the amount of scattering of various concentrations of collagen in gels directly using backscattered light. The results show a highly linear relationship with an increase of 8.2 arbitrary units in backscattering intensity for every 1 mg increase of collagen within a 1 mL gel volume. CONCLUSION The confocal scattered-light scanner allows to accurately quantify scattering in Intralipid and collagen gels. Furthermore, a linear relationship between collagen concentration and intensity was found. Confocal scattered-light scanning therefore promises to allow imaging of collagen content in soft tissue layers.
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Affiliation(s)
- Jeffrey T LaCroix
- University of Missouri, Department of Biological Engineering, Columbia, MO 65211, USA.
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27
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Lane PM, MacAulay CE. Reflection-contrast limit of fiber-optic image guides. JOURNAL OF BIOMEDICAL OPTICS 2009; 14:064028. [PMID: 20059266 PMCID: PMC2801729 DOI: 10.1117/1.3269679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Fiber-optic image guides in confocal reflectance endomicroscopes introduce background backscatter that limits the achievable contrast in these devices. We show the dominant source of backscatter from the image guide is due to Rayleigh scattering at short wavelengths and terminal reflections of the fibers at long wavelengths. The effective Rayleigh scattering coefficient and the wavelength-independent reflectivity due terminal reflections are measured experimentally in a commercial image guide. The Rayleigh scattering component of backscatter can be accurately predicted using the fractional refractive-index difference and length of the fibers in the image guide. We also presented a simple model that can be used to predict signal-to-background ratio in a fiber-optic confocal reflectance endomicroscope for biologically relevant tissues and contrast agents that cover a wide range of reflectivity.
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Affiliation(s)
- Pierre M Lane
- British Columbia Cancer Agency, 675 West 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada.
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Abstract
We present experimental results on optical properties of cranial bone controlled by administration of propylene glycol and glycerol. Both transmittance and reflectance spectra of human and porcine cranial bone in vitro were measured. For estimation of absorption and reduced scattering coefficients of the bone, the inverse adding-doubling method was used. The decrease of reflectance of the samples under action of the immersion agents was demonstrated. The experiments have shown that administration of the immersion liquids allows for effective controlling of tissue optical characteristics that makes bone more transparent, thereby increasing the ability of light penetration through the tissue. The presented results can be used in developing of functional imaging techniques, including OCT.
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29
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Carlson K, Pavlova I, Collier T, Descour M, Follen M, Richards-Kortum R. Confocal microscopy: imaging cervical precancerous lesions. Gynecol Oncol 2005; 99:S84-8. [PMID: 16143376 DOI: 10.1016/j.ygyno.2005.07.049] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVES We explore the clinical potential of reflectance and fluorescence confocal microscopy to image the morphologic and biochemical changes associated with precancer, in order to aid in the detection and diagnosis of cervical dysplasia. METHODS Cervical epithelial tissue samples imaged ex vivo or in vivo were obtained from M. D. Anderson Cancer Center and Lyndon B. Johnson Hospital in Houston, Texas. Confocal reflectance microscopy was used to image ex vivo cervical biopsies and in vivo cervical tissue. Confocal fluorescence microscopy was used to image ex vivo cervical tissue slices. RESULTS We present reflectance and fluorescence confocal images of cervical tissue demonstrating the ability to differentiate between normal and abnormal cervical tissue. CONCLUSIONS We believe that there is significant clinical potential for confocal microscopy to provide a sensitive and specific method for cervical precancer detection.
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Affiliation(s)
- Kristen Carlson
- Department of Biomedical Engineering, 1 University Station, C0800, The University of Texas at Austin, Austin, TX 78712, USA
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Collier T, Follen M, Malpica A, Richards-Kortum R. Sources of scattering in cervical tissue: determination of the scattering coefficient by confocal microscopy. APPLIED OPTICS 2005; 44:2072-81. [PMID: 15835356 DOI: 10.1364/ao.44.002072] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Most models of light propagation through tissue assume that the scattering properties of various tissue layers are the same. We present evidence that the scattering coefficient of cervical epithelium varies by a factor of 3 within the epithelium owing to variations in nuclear density and to the presence of keratin. We estimated the scattering coefficient from regions of normal and precancerous cervical epithelium by fitting reflectance measurements from confocal images to an exponential function of depth based on Beer's law of attenuation. The results suggest that the normal cervix is characterized by highly variable scattering in the superficial epithelium, low scattering in the intermediate epithelium, and high scattering in the basal and stromal regions. In high-grade dysplasia, high scattering from high-density nuclei is observed throughout the entire epithelium.
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Affiliation(s)
- Tom Collier
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
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31
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Loo C, Lowery A, Halas N, West J, Drezek R. Immunotargeted nanoshells for integrated cancer imaging and therapy. NANO LETTERS 2005; 5:709-11. [PMID: 15826113 DOI: 10.1021/nl050127s] [Citation(s) in RCA: 1035] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Nanoshells are a novel class of optically tunable nanoparticles that consist of a dielectric core surrounded by a thin gold shell. Based on the relative dimensions of the shell thickness and core radius, nanoshells may be designed to scatter and/or absorb light over a broad spectral range including the near-infrared (NIR), a wavelength region that provides maximal penetration of light through tissue. The ability to control both wavelength-dependent scattering and absorption of nanoshells offers the opportunity to design nanoshells which provide, in a single nanoparticle, both diagnostic and therapeutic capabilities. Here, we demonstrate a novel nanoshell-based all-optical platform technology for integrating cancer imaging and therapy applications. Immunotargeted nanoshells are engineered to both scatter light in the NIR enabling optical molecular cancer imaging and to absorb light, allowing selective destruction of targeted carcinoma cells through photothermal therapy. In a proof of principle experiment, dual imaging/therapy immunotargeted nanoshells are used to detect and destroy breast carcinoma cells that overexpress HER2, a clinically relevant cancer biomarker.
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Affiliation(s)
- Christopher Loo
- Department of Bioengineering, Rice University, P.O. Box 1892, Houston, Texas 77251-1892, USA
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Gundy S, Van der Putten W, Shearer A, Buckton D, Ryder AG, Ball M. The use of chloroaluminium phthalocyanine tetrasulfonate (AlPcTS) for time-delayed fluorescence imaging. Phys Med Biol 2004; 49:359-69. [PMID: 15012006 DOI: 10.1088/0031-9155/49/3/001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phthalocyanine derivatives are currently under investigation for use in photodynamic therapy, which is a promising cancer treatment. These materials, which display preferential uptake in cancerous cells, also exhibit high fluorescence yields and can be used for tumour detection. Problems with steady-state fluorescence techniques such as excitation scatter and background autofluorescence can be eliminated by using time-resolved imaging techniques without the need for filters. A tissue phantom was assembled to test a constructed time-gated imaging system by drilling 36 wells of varying diameter and depth (10 mm to 1 mm) into a block of polymethyl methacrylate (PMMA). The system was used to record images of chloroaluminium phthalocyanine tetrasulfonate (AlPcTS) at differing concentrations in neat aqueous solvent and cell suspensions within the wells. A mixture of Intralipid (to mimic tissue scatter) and Evan's blue (to mimic tissue absorption) of depths ranging from 1 mm to 10 mm was placed on top of the PMMA block. The ensuing images were analysed using signal-to-noise ratios and contrast-detail curves. The results indicate that the time-gated imaging system can prevent background excitation scatter from distorting the fluorescence signal from a longer-lived photosensitizer without the need for filters.
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Affiliation(s)
- Sarah Gundy
- Department of Information Technology, National University of Ireland, Galway, Republic of Ireland
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McWilliams A, MacAulay C, Gazdar AF, Lam S. Innovative molecular and imaging approaches for the detection of lung cancer and its precursor lesions. Oncogene 2002; 21:6949-59. [PMID: 12362276 DOI: 10.1038/sj.onc.1205831] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Current approaches for the therapy of lung cancer, the majority of which being advanced cancers, have failed to impact on long term survival. The key to improvement lies in the combination of early diagnosis and the introduction of novel targeted therapies. In this article we review some of the innovative approaches, both imaging and molecular, that are currently under investigation for early detection. Because lung cancers may arise in the central or peripheral compartments of the lung, newer approaches must target tumours arising in both of these compartments. Specimens available for analysis include sputa and blood. Detection of genetic changes in peripheral blood is a promising avenue being explored by several groups. Molecular techniques discussed include gene mutations, detection of nuclear riboprotein, methylation related silencing of genes and malignancy associated changes. Newer imaging technologies include autofluorescence bronchoscopy, virtual bronchoscopy, optical coherent tomography and confocal microscopy. Although the impact of these new technologies on survival has not been determined, they offer a wide range of exciting new approaches. In time they may completely revamp the present highly conservative and unsuccessful approaches to early diagnosis.
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Liang C, Sung KB, Richards-Kortum RR, Descour MR. Design of a high-numerical-aperture miniature microscope objective for an endoscopic fiber confocal reflectance microscope. APPLIED OPTICS 2002; 41:4603-10. [PMID: 12153093 DOI: 10.1364/ao.41.004603] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
An endoscopic confocal microscope requires a high-performance, miniaturized microscope objective. We present the design of a miniature water-immersion microscope objective that is approximately 10 times smaller in length than a typical commercial objective. The miniature objective is 7 mm in outer diameter and 21 mm in length (from object to image). It is used in a fiber confocal reflectance microscope. The miniature microscope objective has a numerical aperture of 1.0, a field of view of 250 microm, and a working distance of 450 microm. It delivers diffraction-limited performance at lambda = 1064 nm. Micrometer-level resolution has been experimentally demonstrated.
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Affiliation(s)
- Chen Liang
- Optical Sciences Center, University of Arizona, Tucson 85721, USA.
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Collier T, Lacy A, Richards-Kortum R, Malpica A, Follen M. Near real-time confocal microscopy of amelanotic tissue: detection of dysplasia in ex vivo cervical tissue. Acad Radiol 2002; 9:504-12. [PMID: 12458875 DOI: 10.1016/s1076-6332(03)80326-4] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
RATIONALE AND OBJECTIVES The authors performed this study to determine whether images of ex vivo tissue obtained with a near real-time confocal microscope can be used to differentiate between normal and dysplastic tissue. MATERIALS AND METHODS Biopsy specimens of colposcopically normal and abnormal cervical tissue were obtained from 19 patients and imaged at various depths with a confocal microscope. Nuclear morphologic features were extracted from the confocal images; in addition, a group of reviewers examined the images and attempted to identify whether the specimen contained high-grade dysplasia. Results of both analyses were compared with the histopathologic findings of the same specimens provided by a board-certified pathologist with expertise in gynecologic pathology. RESULTS The morphologic feature measurements compared well with the findings at pathologic examination. The use of the nuclear-cytoplasmic ratio to determine the presence of dysplasia resulted in a sensitivity of 100% and a specificity of 91%. The untrained reviewers had an average sensitivity of 95% and an average specificity of 69% in the determination of dysplasia. CONCLUSION The results indicate the clinical potential of in vivo confocal imaging in the detection of dysplasia.
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Affiliation(s)
- Tom Collier
- Department of Electrical and Computer Engineering, University of Texas at Austin, ENS 610, Austin, TX 78712, USA
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Dunn AK, Wallace VP, Coleno M, Berns MW, Tromberg BJ. Influence of optical properties on two-photon fluorescence imaging in turbid samples. APPLIED OPTICS 2000; 39:1194-201. [PMID: 18338003 DOI: 10.1364/ao.39.001194] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A numerical model was developed to simulate the effects of tissue optical properties, objective numerical aperture (N.A.), and instrument performance on two-photon-excited fluorescence imaging of turbid samples. Model data are compared with measurements of fluorescent microspheres in a tissuelike scattering phantom. Our results show that the measured two-photon-excited signal decays exponentially with increasing focal depth. The overall decay constant is a function of absorption and scattering parameters at both excitation and emission wavelengths. The generation of two-photon fluorescence is shown to be independent of the scattering anisotropy, g, except for g > 0.95. The N.A. for which the maximum signal is collected varies with depth, although this effect is not seen until the focal plane is greater than two scattering mean free paths into the sample. Overall, measurements and model results indicate that resolution in two-photon microscopy is dependent solely on the ability to deliver sufficient ballistic photon density to the focal volume. As a result we show that lateral resolution in two-photon microscopy is largely unaffected by tissue optical properties in the range typically encountered in soft tissues, although the maximum imaging depth is strongly dependent on absorption and scattering coefficients, scattering anisotropy, and objective N.A..
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Affiliation(s)
- A K Dunn
- Laser Medical and Microbeam Program, Beckman Laser Institute, University of California, Irvine, California 92612, USA
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Collier T, Shen P, de Pradier B, Sung KB, Richards-Kortum R, Follen M, Malpica A. Near real time confocal microscopy of amelanotic tissue: dynamics of aceto-whitening enable nuclear segmentation. OPTICS EXPRESS 2000; 6:40-8. [PMID: 19401743 DOI: 10.1364/oe.6.000040] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
High resolution, in vivo confocal imaging of amelanotic epithelial tissue may offer a clinically useful adjunct to standard histopathologic techniques. Application of acetic acid has been shown to enhance contrast in confocal images of these tissues. In this study, we record the time course of aceto-whitening at the cellular level and determine whether the contrast provided enables quantitative feature analysis. Confocal images and videos of cervical specimens were obtained throughout the epithelium before, during and post-acetic acid after the application of 6% acetic acid. Aceto-whitening occurs within seconds after the application. The confocal imaging system resolved sub-cellular detail throughout the entire epithelial thickness and provided sufficient contrast to enable quantitative feature analysis.
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Podoleanu AG. Unbalanced versus balanced operation in an optical coherence tomography system. APPLIED OPTICS 2000; 39:173-82. [PMID: 18337886 DOI: 10.1364/ao.39.000173] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The choice of a balanced optical coherence tomography (OCT) configuration versus an unbalanced OCT configuration with optimized reference-arm attenuation is discussed. The choice depends on the receiver noise, the fiber-end reflection R, and the power to the object. When OCT is used to investigate biological tissue an equivalent R? can be evaluated as the compound reflected light from tissue. In this case an additional parameter has to be considered: the confocal optical sectioning interval of the OCT system.
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Affiliation(s)
- A G Podoleanu
- Applied Optics Group, School of Physical Sciences, University of Kent, Canterbury CT2 7NR, United Kingdom.
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