1
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Pfeiffer T, Petermann M, Draxinger W, Jirauschek C, Huber R. Ultra low noise Fourier domain mode locked laser for high quality megahertz optical coherence tomography. Biomed Opt Express 2018; 9:4130-4148. [PMID: 30615700 PMCID: PMC6157755 DOI: 10.1364/boe.9.004130] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/16/2018] [Accepted: 07/16/2018] [Indexed: 05/28/2023]
Abstract
We investigate the origin of high frequency noise in Fourier domain mode locked (FDML) lasers and present an extremely well dispersion compensated setup which virtually eliminates intensity noise and dramatically improves coherence properties. We show optical coherence tomography (OCT) imaging at 3.2 MHz A-scan rate and demonstrate the positive impact of the described improvements on the image quality. Especially in highly scattering samples, at specular reflections and for strong signals at large depth, the noise in optical coherence tomography images is significantly reduced. We also describe a simple model that suggests a passive physical stabilizing mechanism that leads to an automatic compensation of remaining cavity dispersion in FDML lasers.
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Affiliation(s)
- Tom Pfeiffer
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
- Medizinisches Laserzentrum Lübeck GmbH, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | | | - Wolfgang Draxinger
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
- Medizinisches Laserzentrum Lübeck GmbH, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Christian Jirauschek
- Department of Electrical and Computer Engineering, Technical University of Munich (TUM), Arcisstraße 21, 80333 Munich, Germany
| | - Robert Huber
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
- Medizinisches Laserzentrum Lübeck GmbH, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
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2
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Alfonso-Garcia A, Haudenschild AK, Marcu L. Label-free assessment of carotid artery biochemical composition using fiber-based fluorescence lifetime imaging. Biomed Opt Express 2018; 9:4064-4076. [PMID: 30615748 PMCID: PMC6157793 DOI: 10.1364/boe.9.004064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 07/11/2018] [Accepted: 07/12/2018] [Indexed: 05/08/2023]
Abstract
Novel diagnostic tools with the ability to monitor variations in biochemical composition and provide benchmark indicators of vascular tissue maturation are needed to create functional tissue replacements. We investigated the ability of fiber-based, label-free multispectral fluorescent lifetime imaging (FLIm) to quantify the anatomical variations in biochemical composition of native carotid arteries and validated these results against biochemical assays. FLIm-derived parameters in spectral band 415-455 nm correlated with tissue collagen content (R2 = 0.64) and cell number (R2 = 0.61) and in spectral band 465-553 nm strongly correlated with elastin content (R2 = 0.89). These results suggest that FLIm holds great potential for assessing vascular tissue maturation and functional properties based on tissue autofluorescence.
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Affiliation(s)
- Alba Alfonso-Garcia
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
- Authors contributed equally to this work
| | - Anne K. Haudenschild
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
- Authors contributed equally to this work
| | - Laura Marcu
- Department of Biomedical Engineering, University of California, Davis, 451 E. Health Sciences Dr., Davis, CA 95616,
USA
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3
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Eugui P, Lichtenegger A, Augustin M, Harper DJ, Muck M, Roetzer T, Wartak A, Konegger T, Widhalm G, Hitzenberger CK, Woehrer A, Baumann B. Beyond backscattering: optical neuroimaging by BRAD. Biomed Opt Express 2018; 9:2476-2494. [PMID: 30258667 PMCID: PMC6154182 DOI: 10.1364/boe.9.002476] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/13/2018] [Accepted: 04/26/2018] [Indexed: 05/20/2023]
Abstract
Optical coherence tomography (OCT) is a powerful technology for rapid volumetric imaging in biomedicine. The bright field imaging approach of conventional OCT systems is based on the detection of directly backscattered light, thereby waiving the wealth of information contained in the angular scattering distribution. Here we demonstrate that the unique features of few-mode fibers (FMF) enable simultaneous bright and dark field (BRAD) imaging for OCT. As backscattered light is picked up by the different modes of a FMF depending upon the angular scattering pattern, we obtain access to the directional scattering signatures of different tissues by decoupling illumination and detection paths. We exploit the distinct modal propagation properties of the FMF in concert with the long coherence lengths provided by modern wavelength-swept lasers to achieve multiplexing of the different modal responses into a combined OCT tomogram. We demonstrate BRAD sensing for distinguishing differently sized microparticles and showcase the performance of BRAD-OCT imaging with enhanced contrast for ex vivo tumorous tissue in glioblastoma and neuritic plaques in Alzheimer's disease.
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Affiliation(s)
- Pablo Eugui
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Antonia Lichtenegger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Danielle J. Harper
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Martina Muck
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
- Institute of Neurology, General Hospital and Medical University of Vienna, Vienna,
Austria
| | - Thomas Roetzer
- Institute of Neurology, General Hospital and Medical University of Vienna, Vienna,
Austria
| | - Andreas Wartak
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Thomas Konegger
- Institute of Chemical Technologies and Analytics, TU Wien, Vienna,
Austria
| | - Georg Widhalm
- Department of Neurosurgery, General Hospital and Medical University of Vienna, Vienna,
Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
| | - Adelheid Woehrer
- Institute of Neurology, General Hospital and Medical University of Vienna, Vienna,
Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna,
Austria
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4
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Ohayon S, Caravaca-Aguirre A, Piestun R, DiCarlo JJ. Minimally invasive multimode optical fiber microendoscope for deep brain fluorescence imaging. Biomed Opt Express 2018; 9:1492-1509. [PMID: 29675297 PMCID: PMC5905901 DOI: 10.1364/boe.9.001492] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/22/2018] [Accepted: 02/23/2018] [Indexed: 05/20/2023]
Abstract
A major open challenge in neuroscience is the ability to measure and perturb neural activity in vivo from well defined neural sub-populations at cellular resolution anywhere in the brain. However, limitations posed by scattering and absorption prohibit non-invasive multi-photon approaches for deep (>2mm) structures, while gradient refractive index (GRIN) endoscopes are relatively thick and can cause significant damage upon insertion. Here, we present a novel micro-endoscope design to image neural activity at arbitrary depths via an ultra-thin multi-mode optical fiber (MMF) probe that has 5-10X thinner diameter than commercially available micro-endoscopes. We demonstrate micron-scale resolution, multi-spectral and volumetric imaging. In contrast to previous approaches, we show that this method has an improved acquisition speed that is sufficient to capture rapid neuronal dynamics in-vivo in rodents expressing a genetically encoded calcium indicator (GCaMP). Our results emphasize the potential of this technology in neuroscience applications and open up possibilities for cellular resolution imaging in previously unreachable brain regions.
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Affiliation(s)
- Shay Ohayon
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139,
USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139,
USA
| | - Antonio Caravaca-Aguirre
- Department of Electrical, Computer and Energy Engineering, University of Colorado, Boulder, CO 80309,
USA
| | - Rafael Piestun
- Department of Electrical, Computer and Energy Engineering, University of Colorado, Boulder, CO 80309,
USA
| | - James J. DiCarlo
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, 43 Vassar Street, Cambridge, MA 02139,
USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139,
USA
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5
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Chong SP, Zhang T, Kho A, Bernucci MT, Dubra A, Srinivasan VJ. Ultrahigh resolution retinal imaging by visible light OCT with longitudinal achromatization. Biomed Opt Express 2018; 9:1477-1491. [PMID: 29675296 PMCID: PMC5905900 DOI: 10.1364/boe.9.001477] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 01/30/2018] [Accepted: 02/03/2018] [Indexed: 05/18/2023]
Abstract
Chromatic aberrations are an important design consideration in high resolution, high bandwidth, refractive imaging systems that use visible light. Here, we present a fiber-based spectral/Fourier domain, visible light OCT ophthalmoscope corrected for the average longitudinal chromatic aberration (LCA) of the human eye. Analysis of complex speckles from in vivo retinal images showed that achromatization resulted in a speckle autocorrelation function that was ~20% narrower in the axial direction, but unchanged in the transverse direction. In images from the improved, achromatized system, the separation between Bruch's membrane (BM), the retinal pigment epithelium (RPE), and the outer segment tips clearly emerged across the entire 6.5 mm field-of-view, enabling segmentation and morphometry of BM and the RPE in a human subject. Finally, cross-sectional images depicted distinct inner retinal layers with high resolution. Thus, with chromatic aberration compensation, visible light OCT can achieve volume resolutions and retinal image quality that matches or exceeds ultrahigh resolution near-infrared OCT systems with no monochromatic aberration compensation.
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Affiliation(s)
- Shau Poh Chong
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Equal contributions
| | - Tingwei Zhang
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Equal contributions
| | - Aaron Kho
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
| | - Marcel T. Bernucci
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
| | - Alfredo Dubra
- Byers Eye Institute, Stanford University, Palo Alto, CA 94303, USA
| | - Vivek J. Srinivasan
- Biomedical Engineering Department, University of California Davis, Davis, CA 95616, USA
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, CA 95817, USA
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6
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Mekhail SP, Abudukeyoumu N, Ward J, Arbuthnott G, Chormaic SN. Fiber-bundle-basis sparse reconstruction for high resolution wide-field microendoscopy. Biomed Opt Express 2018; 9:1843-1851. [PMID: 29675323 PMCID: PMC5905928 DOI: 10.1364/boe.9.001843] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/27/2018] [Accepted: 02/28/2018] [Indexed: 05/14/2023]
Abstract
In order to observe deep regions of the brain, we propose the use of a fiber bundle for microendoscopy. Fiber bundles allow for the excitation and collection of fluorescence as well as wide field imaging while remaining largely impervious to image distortions brought on by bending. Furthermore, their thin diameter, from 200-500 µm, means their impact on living tissue, though not absent, is minimal. Although wide field imaging with a bundle allows for a high temporal resolution since no scanning is involved, the largest criticism of bundle imaging is the drastically lowered spatial resolution. In this paper, we make use of sparsity in the object being imaged to up sample the low resolution images from the fiber bundle with compressive sensing. We take each image in a single shot by using a measurement basis dictated by the quasi-crystalline arrangement of the bundle's cores. We find that this technique allows us to increase the resolution of a typical image taken through a fiber bundle.
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Affiliation(s)
- Simon Peter Mekhail
- Light-Matter Interactions Unit, Okinawa Institute of Science and Technology Graduate University, Onna,
Japan
| | - Nilupaer Abudukeyoumu
- Brain Mechanisms for Behaviour Unit, Okinawa Institute of Science and Technology Graduate University, Onna,
Japan
| | - Jonathan Ward
- Light-Matter Interactions Unit, Okinawa Institute of Science and Technology Graduate University, Onna,
Japan
| | - Gordon Arbuthnott
- Brain Mechanisms for Behaviour Unit, Okinawa Institute of Science and Technology Graduate University, Onna,
Japan
| | - Síle Nic Chormaic
- Light-Matter Interactions Unit, Okinawa Institute of Science and Technology Graduate University, Onna,
Japan
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7
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Eibl M, Karpf S, Weng D, Hakert H, Pfeiffer T, Kolb JP, Huber R. Single pulse two photon fluorescence lifetime imaging (SP-FLIM) with MHz pixel rate. Biomed Opt Express 2017; 8:3132-3142. [PMID: 28717558 PMCID: PMC5508819 DOI: 10.1364/boe.8.003132] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/05/2017] [Accepted: 05/08/2017] [Indexed: 05/18/2023]
Abstract
Two-photon-excited fluorescence lifetime imaging microscopy (FLIM) is a chemically specific 3-D sensing modality providing valuable information about the microstructure, composition and function of a sample. However, a more widespread application of this technique is hindered by the need for a sophisticated ultra-short pulse laser source and by speed limitations of current FLIM detection systems. To overcome these limitations, we combined a robust sub-nanosecond fiber laser as the excitation source with high analog bandwidth detection. Due to the long pulse length in our configuration, more fluorescence photons are generated per pulse, which allows us to derive the lifetime with a single excitation pulse only. In this paper, we show high quality FLIM images acquired at a pixel rate of 1 MHz. This approach is a promising candidate for an easy-to-use and benchtop FLIM system to make this technique available to a wider research community.
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Affiliation(s)
- Matthias Eibl
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Sebastian Karpf
- Department of Electrical Engineering, University of California, Los Angeles, CA 90095, USA
| | - Daniel Weng
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Hubertus Hakert
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Tom Pfeiffer
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Jan Philip Kolb
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Robert Huber
- Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
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8
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Chong SP, Bernucci M, Radhakrishnan H, Srinivasan VJ. Structural and functional human retinal imaging with a fiber-based visible light OCT ophthalmoscope. Biomed Opt Express 2017; 8:323-337. [PMID: 28101421 PMCID: PMC5231302 DOI: 10.1364/boe.8.000323] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 12/13/2016] [Accepted: 12/13/2016] [Indexed: 05/18/2023]
Abstract
The design of a multi-functional fiber-based Optical Coherence Tomography (OCT) system for human retinal imaging with < 2 micron axial resolution in tissue is described. A detailed noise characterization of two supercontinuum light sources with different pulse repetition rates is presented. The higher repetition rate and lower noise source is found to enable a sensitivity of 96 dB with 0.15 mW light power at the cornea and a 98 microsecond exposure time. Using a broadband (560 ± 50 nm), 90/10, fused single-mode fiber coupler designed for visible wavelengths, the sample arm is integrated into an ophthalmoscope platform, similar to current clinical OCT systems. To demonstrate the instrument's range of operation, in vivo structural retinal imaging is also shown at 0.15 mW exposure with 10,000 and 70,000 axial scans per second (the latter comparable to commercial OCT systems), and at 0.03 mW exposure and 10,000 axial scans per second (below maximum permissible continuous exposure levels). Lastly, in vivo spectroscopic imaging of anatomy, saturation, and hemoglobin content in the human retina is also demonstrated.
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Affiliation(s)
- Shau Poh Chong
- Biomedical Engineering Department, University of California Davis, Davis, California 95616,
USA
| | - Marcel Bernucci
- Biomedical Engineering Department, University of California Davis, Davis, California 95616,
USA
| | - Harsha Radhakrishnan
- Biomedical Engineering Department, University of California Davis, Davis, California 95616,
USA
| | - Vivek J. Srinivasan
- Biomedical Engineering Department, University of California Davis, Davis, California 95616,
USA
- Department of Ophthalmology and Vision Science, University of California Davis School of Medicine, Sacramento, California 95817,
USA
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9
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Wei X, Kong C, Sy S, Ko H, Tsia KK, Wong KKY. Ultrafast time-stretch imaging at 932 nm through a new highly-dispersive fiber. Biomed Opt Express 2016; 7:5208-5217. [PMID: 28018737 PMCID: PMC5175564 DOI: 10.1364/boe.7.005208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/12/2016] [Accepted: 11/12/2016] [Indexed: 05/25/2023]
Abstract
Optical glass fiber has played a key role in the development of modern optical communication and attracted the biotechnology researcher's great attention because of its properties, such as the wide bandwidth, low attenuation and superior flexibility. For ultrafast optical imaging, particularly, it has been utilized to perform MHz time-stretch imaging with diffraction-limited resolutions, which is also known as serial time-encoded amplified microscopy (STEAM). Unfortunately, time-stretch imaging with dispersive fibers has so far mostly been demonstrated at the optical communication window of 1.5 μm due to lack of efficient dispersive optical fibers operating at the shorter wavelengths, particularly at the bio-favorable window, i.e., <1.0 μm. Through fiber-optic engineering, here we demonstrate a 7.6-MHz dual-color time-stretch optical imaging at bio-favorable wavelengths of 932 nm and 466 nm. The sensitivity at such a high speed is experimentally identified in a slow data-streaming manner. To the best of our knowledge, this is the first time that all-optical time-stretch imaging at ultrahigh speed, high sensitivity and high chirping rate (>1 ns/nm) has been demonstrated at a bio-favorable wavelength window through fiber-optic engineering.
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Affiliation(s)
- Xiaoming Wei
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Cihang Kong
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Samuel Sy
- Department of Electronic Engineering, Faculty of Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Ho Ko
- Department of Medicine and Therapeutics, Prince of Wales Hospital, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, China
- Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Kevin K. Tsia
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Kenneth K. Y. Wong
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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10
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Karpf S, Eibl M, Sauer B, Reinholz F, Hüttmann G, Huber R. Two-photon microscopy using fiber-based nanosecond excitation. Biomed Opt Express 2016; 7:2432-40. [PMID: 27446680 PMCID: PMC4948604 DOI: 10.1364/boe.7.002432] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/10/2016] [Accepted: 04/20/2016] [Indexed: 05/18/2023]
Abstract
Two-photon excitation fluorescence (TPEF) microscopy is a powerful technique for sensitive tissue imaging at depths of up to 1000 micrometers. However, due to the shallow penetration, for in vivo imaging of internal organs in patients beam delivery by an endoscope is crucial. Until today, this is hindered by linear and non-linear pulse broadening of the femtosecond pulses in the optical fibers of the endoscopes. Here we present an endoscope-ready, fiber-based TPEF microscope, using nanosecond pulses at low repetition rates instead of femtosecond pulses. These nanosecond pulses lack most of the problems connected with femtosecond pulses but are equally suited for TPEF imaging. We derive and demonstrate that at given cw-power the TPEF signal only depends on the duty cycle of the laser source. Due to the higher pulse energy at the same peak power we can also demonstrate single shot two-photon fluorescence lifetime measurements.
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Affiliation(s)
- Sebastian Karpf
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
- Department of Electrical Engineering, University of California, Los Angeles, California 90095, USA
| | - Matthias Eibl
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Benjamin Sauer
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Fred Reinholz
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Gereon Hüttmann
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
| | - Robert Huber
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany
- Institut für Biomedizinische Optik, Universität zu Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
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11
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Qiu Y, Wang Y, Belfield KD, Liu X. Ultrathin lensed fiber-optic probe for optical coherence tomography. Biomed Opt Express 2016; 7:2154-2162. [PMID: 27375934 PMCID: PMC4918572 DOI: 10.1364/boe.7.002154] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 05/05/2016] [Accepted: 05/05/2016] [Indexed: 05/30/2023]
Abstract
We investigated and validated a novel method to develop ultrathin lensed fiber-optic (LFO) probes for optical coherence tomography (OCT) imaging. We made the LFO probe by attaching a segment of no core fiber (NCF) to the distal end of a single mode fiber (SMF) and generating a curved surface at the tip of the NCF using the electric arc of a fusion splicer. The novel fabrication approach enabled us to control the length of the NCF and the radius of the fiber lens independently. By strategically choosing these two parameters, the LFO probe could achieve a broad range of working distance and depth of focus for different OCT applications. A probe with 125μm diameter and lateral resolution up to 10μm was demonstrated. The low-cost, disposable and robust LFO probe is expected to have great potential for interstitial OCT imaging.
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Affiliation(s)
- Y. Qiu
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Y. Wang
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - K. D. Belfield
- College of Science and Liberal Arts, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - X. Liu
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
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12
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Kang J, Wei X, Li B, Wang X, Yu L, Tan S, Jinata C, Wong KKY. Sensitivity enhancement in swept-source optical coherence tomography by parametric balanced detector and amplifier. Biomed Opt Express 2016; 7:1294-304. [PMID: 27446655 PMCID: PMC4929641 DOI: 10.1364/boe.7.001294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 03/07/2016] [Accepted: 03/08/2016] [Indexed: 05/22/2023]
Abstract
We proposed a sensitivity enhancement method of the interference-based signal detection approach and applied it on a swept-source optical coherence tomography (SS-OCT) system through all-fiber optical parametric amplifier (FOPA) and parametric balanced detector (BD). The parametric BD was realized by combining the signal and phase conjugated idler band that was newly-generated through FOPA, and specifically by superimposing these two bands at a photodetector. The sensitivity enhancement by FOPA and parametric BD in SS-OCT were demonstrated experimentally. The results show that SS-OCT with FOPA and SS-OCT with parametric BD can provide more than 9 dB and 12 dB sensitivity improvement, respectively, when compared with the conventional SS-OCT in a spectral bandwidth spanning over 76 nm. To further verify and elaborate their sensitivity enhancement, a bio-sample imaging experiment was conducted on loach eyes by conventional SS-OCT setup, SS-OCT with FOPA and parametric BD at different illumination power levels. All these results proved that using FOPA and parametric BD could improve the sensitivity significantly in SS-OCT systems.
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13
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Zeidan A, Yelin D. Spectral imaging using forward-viewing spectrally encoded endoscopy. Biomed Opt Express 2016; 7:392-8. [PMID: 26977348 PMCID: PMC4771457 DOI: 10.1364/boe.7.000392] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 12/27/2015] [Accepted: 01/04/2016] [Indexed: 05/24/2023]
Abstract
Spectrally encoded endoscopy (SEE) enables miniature, small-diameter endoscopic probes for minimally invasive imaging; however, using the broadband spectrum to encode space makes color and spectral imaging nontrivial and challenging. By careful registration and analysis of image data acquired by a prototype of a forward-viewing dual channel spectrally encoded rigid probe, we demonstrate spectral and color imaging within a narrow cylindrical lumen. Spectral imaging of calibration cylindrical test targets and an ex-vivo blood vessel demonstrates high-resolution spatial-spectral imaging with short (10 μs/line) exposure times.
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14
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Stasio N, Shibukawa A, Papadopoulos IN, Farahi S, Simandoux O, Huignard JP, Bossy E, Moser C, Psaltis D. Towards new applications using capillary waveguides. Biomed Opt Express 2015; 6:4619-31. [PMID: 26713182 PMCID: PMC4679242 DOI: 10.1364/boe.6.004619] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 10/26/2015] [Accepted: 10/29/2015] [Indexed: 05/10/2023]
Abstract
In this paper we demonstrate the enhancement of the sensing capabilities of glass capillaries. We exploit their properties as optical and acoustic waveguides to transform them potentially into high resolution minimally invasive endoscopic devices. We show two possible applications of silica capillary waveguides demonstrating fluorescence and optical-resolution photoacoustic imaging using a single 330 μm-thick silica capillary. A nanosecond pulsed laser is focused and scanned in front of a capillary by digital phase conjugation through the silica annular ring of the capillary, used as an optical waveguide. We demonstrate optical-resolution photoacoustic images of a 30 μm-thick nylon thread using the water-filled core of the same capillary as an acoustic waveguide, resulting in a fully passive endoscopic device. Moreover, fluorescence images of 1.5 μm beads are obtained collecting the fluorescence signal through the optical waveguide. This kind of silica-capillary waveguide together with wavefront shaping techniques such as digital phase conjugation, paves the way to minimally invasive multi-modal endoscopy.
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Affiliation(s)
- Nicolino Stasio
- Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
- contributed equally
| | - Atsushi Shibukawa
- Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
- contributed equally
| | - Ioannis N. Papadopoulos
- Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
| | - Salma Farahi
- Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
- Laboratory of Applied Photonics Devices, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
| | - Olivier Simandoux
- ESPCI ParisTech, PSL Research University, CNRS, INSERM, Institut Langevin, 1 rue Jussieu, 75005 Paris,
France
| | | | - Emmanuel Bossy
- ESPCI ParisTech, PSL Research University, CNRS, INSERM, Institut Langevin, 1 rue Jussieu, 75005 Paris,
France
| | - Christophe Moser
- Laboratory of Applied Photonics Devices, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
| | - Demetri Psaltis
- Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne,
Switzerland
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15
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Guo Q, Chen H, Weng Z, Chen M, Yang S, Xie S. Fast time-lens-based line-scan single-pixel camera with multi-wavelength source. Biomed Opt Express 2015; 6:3610-7. [PMID: 26417527 PMCID: PMC4574683 DOI: 10.1364/boe.6.003610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 08/21/2015] [Accepted: 08/24/2015] [Indexed: 05/26/2023]
Abstract
A fast time-lens-based line-scan single-pixel camera with multi-wavelength source is proposed and experimentally demonstrated in this paper. A multi-wavelength laser instead of a mode-locked laser is used as the optical source. With a diffraction grating and dispersion compensating fibers, the spatial information of an object is converted into temporal waveforms which are then randomly encoded, temporally compressed and captured by a single-pixel photodetector. Two algorithms (the dictionary learning algorithm and the discrete cosine transform-based algorithm) for image reconstruction are employed, respectively. Results show that the dictionary learning algorithm has greater capability to reduce the number of compressive measurements than the DCT-based algorithm. The effective imaging frame rate increases from 200 kHz to 1 MHz, which shows a significant improvement in imaging speed over conventional single-pixel cameras.
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16
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Duan X, Li H, Qiu Z, Joshi BP, Pant A, Smith A, Kurabayashi K, Oldham KR, Wang TD. MEMS-based multiphoton endomicroscope for repetitive imaging of mouse colon. Biomed Opt Express 2015; 6:3074-83. [PMID: 26309768 PMCID: PMC4541532 DOI: 10.1364/boe.6.003074] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 07/03/2015] [Accepted: 07/21/2015] [Indexed: 05/08/2023]
Abstract
We demonstrate a handheld multiphoton endomicroscope with 3.4 mm distal diameter that can repetitively image mouse colon in vivo. A 2D resonant MEMS mirror was developed to perform beam scanning in a Lissajous pattern. The instrument has an effective numerical aperture of 0.63, lateral and axial resolution of 2.03 and 9.02 μm, respectively, working distance of 60 μm, and image field-of-view of 300 × 300 μm(2). Hoechst was injected intravenously in mice to stain cell nuclei. We were able to collect histology-like images in vivo at 5 frames/sec, and distinguish between normal and pre-malignant colonic epithelium.
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Affiliation(s)
- Xiyu Duan
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Haijun Li
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Zhen Qiu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Bishnu P. Joshi
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Asha Pant
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Arlene Smith
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
| | - Katsuo Kurabayashi
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Electrical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Kenn R. Oldham
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Thomas D. Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Internal Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI, USA
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
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17
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Lee J, Chae Y, Ahn YC, Moon S. Ultra-thin and flexible endoscopy probe for optical coherence tomography based on stepwise transitional core fiber. Biomed Opt Express 2015; 6:1782-96. [PMID: 26137380 PMCID: PMC4467695 DOI: 10.1364/boe.6.001782] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 04/09/2015] [Accepted: 04/16/2015] [Indexed: 05/18/2023]
Abstract
We present an ultra-thin fiber-body endoscopy probe for optical coherence tomography (OCT) which is based on a stepwise transitional core (STC) fiber. In a minimalistic design, our probe was made of spliced specialty fibers that could be directly used for beam probing optics without using a lens. In our probe, the OCT light delivered through a single-mode fiber was efficiently expanded to a large mode field of 24 μm diameter for a low beam divergence. The size of our probe was 85 μm in the probe's diameter while operated in a 160-μm thick protective tubing. Through theoretical and experimental analyses, our probe was found to exhibit various attractive features in terms of compactness, flexibility and reliability along with its excellent fabrication simplicity.
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Affiliation(s)
- Jangbeom Lee
- Department of Physics, Kookmin University, Seoul, 136-702,
South Korea
| | - Yugyeong Chae
- Department of Biomedical Engineering and Center for Marine-Integrated Biomedical Technology, Pukyong National University, Busan, 608-737,
South Korea
| | - Yeh-Chan Ahn
- Department of Biomedical Engineering and Center for Marine-Integrated Biomedical Technology, Pukyong National University, Busan, 608-737,
South Korea
| | - Sucbei Moon
- Department of Physics, Kookmin University, Seoul, 136-702,
South Korea
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18
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Keahey PA, Tkaczyk TS, Schmeler KM, Richards-Kortum RR. Optimizing modulation frequency for structured illumination in a fiber-optic microendoscope to image nuclear morphometry in columnar epithelium. Biomed Opt Express 2015; 6:870-80. [PMID: 25798311 PMCID: PMC4361441 DOI: 10.1364/boe.6.000870] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 02/09/2015] [Accepted: 02/14/2015] [Indexed: 05/08/2023]
Abstract
Fiber-optic microendoscopes have shown promise to image the changes in nuclear morphometry that accompany the development of precancerous lesions in tissue with squamous epithelium such as in the oral mucosa and cervix. However, fiber-optic microendoscopy image contrast is limited by out-of-focus light generated by scattering within tissue. The scattering coefficient of tissues with columnar epithelium can be greater than that of squamous epithelium resulting in decreased image quality. To address this challenge, we present a small and portable microendoscope system capable of performing optical sectioning using structured illumination (SI) in real-time. Several optical phantoms were developed and used to quantify the sectioning capabilities of the system. Columnar epithelium from cervical tissue specimens was then imaged ex vivo, and we demonstrate that the addition of SI achieves higher image contrast, enabling visualization of nuclear morphology.
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Affiliation(s)
- P. A. Keahey
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77025
USA
| | - T. S. Tkaczyk
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77025
USA
| | - K. M. Schmeler
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, 1100 Holcombe Boulevard, Houston, TX 77030
USA
| | - R. R. Richards-Kortum
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, Texas 77025
USA
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19
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Cha J, Zhang J, Gurbani S, Cheon GW, Li M, Kang JU. Gene transfection efficacy assessment of human cervical cancer cells using dual-mode fluorescence microendoscopy. Biomed Opt Express 2013; 4:151-159. [PMID: 23304654 PMCID: PMC3539186 DOI: 10.1364/boe.4.000151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 12/10/2012] [Accepted: 12/12/2012] [Indexed: 06/01/2023]
Abstract
We report a novel approach to quantitatively assess gene transfection efficacy using dual-modality microendoscopy that can simultaneously monitor both laser scanning reflectance and fluorescence imaging. The system uses a 500-μm-diameter coherent fiber bundle and permits 3.5-μm lateral resolution. Both reflectance and fluorescence images obtained from two silicon avalanche photodetectors are displaying at 1 Hz and processed automatically to calculate gene transfection efficiency (the ratio of fluorescent cells among the total cells). To validate the system performance we examined the expression of cyan fluorescent protein using human cervical cancer cells (HeLa) in four commercially available reagents. The result was compared with that using a high-resolution bench-top microscope.
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Affiliation(s)
- Jaepyeong Cha
- Department of Electrical and Computer Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
| | - Jing Zhang
- Department of Neuroscience, School of Medicine, Johns Hopkins University, 733 North Broadway, Baltimore, MD 21205, USA
| | - Saumya Gurbani
- Department of Electrical and Computer Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
- Department of Biomedical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
| | - Gyeong Woo Cheon
- Department of Electrical and Computer Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
| | - Min Li
- Department of Neuroscience, School of Medicine, Johns Hopkins University, 733 North Broadway, Baltimore, MD 21205, USA
| | - Jin U. Kang
- Department of Electrical and Computer Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
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20
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Tan KM, Shishkov M, Chee A, Applegate MB, Bouma BE, Suter MJ. Flexible transbronchial optical frequency domain imaging smart needle for biopsy guidance. Biomed Opt Express 2012; 3:1947-54. [PMID: 22876357 PMCID: PMC3409712 DOI: 10.1364/boe.3.001947] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 07/26/2012] [Accepted: 07/27/2012] [Indexed: 05/12/2023]
Abstract
Transbronchial needle aspiration (TBNA) is a procedure routinely performed to diagnose peripheral pulmonary lesions. However, TBNA is associated with a low diagnostic yield due to inappropriate needle placement. We have developed a flexible transbronchial optical frequency domain imaging (TB-OFDI) catheter that functions as a "smart needle" to confirm the needle placement within the target lesion prior to biopsy. The TB-OFDI smart needle consists of a flexible and removable OFDI catheter (430 µm dia.) that operates within a standard 21-gauge TBNA needle. The OFDI imaging core is based on an angle polished ball lens design with a working distance of 160 µm from the catheter sheath and a spot size of 25 µm. To demonstrate the potential of the TB-OFDI smart needle for transbronchial imaging, an inflated excised swine lung was imaged through a standard bronchoscope. Cross-sectional and longitudinal OFDI results reveal the detailed network of alveoli in the lung parenchyma suggesting that the TB-OFDI smart needle may be a useful tool for guiding biopsy acquisition to increase the diagnostic yield.
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Affiliation(s)
- K. M. Tan
- Department of Medicine, Pulmonary and Critical Care Unit, Massachusetts General Hospital, 40 Blossom Street, Boston, Massachusetts, 02114, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts, 02115, USA
| | - M. Shishkov
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts, 02115, USA
| | - A. Chee
- Department of Medicine, Pulmonary and Critical Care Unit, Massachusetts General Hospital, 40 Blossom Street, Boston, Massachusetts, 02114, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts, 02115, USA
| | - M. B. Applegate
- Department of Medicine, Pulmonary and Critical Care Unit, Massachusetts General Hospital, 40 Blossom Street, Boston, Massachusetts, 02114, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
| | - B. E. Bouma
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts, 02115, USA
- Equal contribution
| | - M. J. Suter
- Department of Medicine, Pulmonary and Critical Care Unit, Massachusetts General Hospital, 40 Blossom Street, Boston, Massachusetts, 02114, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts, 02114, USA
- Harvard Medical School, 25 Shattuck Street, Boston, Massachusetts, 02115, USA
- Equal contribution
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21
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Mufti N, Kong Y, Cirillo JD, Maitland KC. Fiber optic microendoscopy for preclinical study of bacterial infection dynamics. Biomed Opt Express 2011; 2:1121-34. [PMID: 21559125 PMCID: PMC3087570 DOI: 10.1364/boe.2.001121] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 04/02/2011] [Accepted: 04/04/2011] [Indexed: 05/04/2023]
Abstract
We explore the use of fiber optic microendoscopy to image and quantify bacterial infection in the skin and lungs using an animal model. The contact probe fiber bundle fluorescence microendoscope has a 4 µm resolution, a 750 µm field of view, and a 1 mm outer diameter. Subcutaneous and intra-tracheal infections of fluorescent Mycobacterium bovis Bacillus Calmette-Guérin (BCG) bacteria were detected in situ from inocula down to 10(4) and 10(7) colony forming units, respectively.
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Affiliation(s)
- Nooman Mufti
- Department of Biomedical Engineering, Texas A&M University, 337 Zachry Engineering Center, 3120 TAMU, College Station, TX 77843, USA
- These authors contributed equally to this work
| | - Ying Kong
- Department of Microbial and Molecular Pathogenesis, Texas A&M Health Science Center, 467 Reynolds Medical Building, College Station, TX, 77843, USA
- These authors contributed equally to this work
| | - Jeffrey D. Cirillo
- Department of Microbial and Molecular Pathogenesis, Texas A&M Health Science Center, 467 Reynolds Medical Building, College Station, TX, 77843, USA
| | - Kristen C. Maitland
- Department of Biomedical Engineering, Texas A&M University, 337 Zachry Engineering Center, 3120 TAMU, College Station, TX 77843, USA
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