1. Articles from Biwei Yin

    1-19 of 19
    1. Stromal Nerve Imaging and Tracking Using Micro-Optical Coherence Tomography

      Stromal Nerve Imaging and Tracking Using Micro-Optical Coherence Tomography

      urpose : To image, track and map the nerve fiber distribution in excised rabbit corneas over the entire stromal thickness using micro-optical coherence tomography (µOCT) to develop a screening tool for early peripheral neuropathy. Methods : Excised rabbit corneas were consecutively imaged by a custom-designed µOCT prototype and a commercial laser scanning fluorescence confocal microscope. The µOCT images with a field of view of approximately 1 × 1 mm were recorded with axial and transverse resolutions of approximately 1 µm and approximately 4 µm, respectively. In the volumetric µOCT image data, network maps of hyper-reflective, branched structures traversing different stromal compartments were segmented ...

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    2. Apparatus and methods for mirror tunnel imaging device and for providing pseudobessel beams in a miniaturized optical system for imaging

      Apparatus and methods for mirror tunnel imaging device and for providing pseudobessel beams in a miniaturized optical system for imaging

      Exemplary apparatus and method are provided for illuminating a sample. With such exemplary apparatus and/or method, it is possible to, using at least one source arrangement, provide at least one first electro-magnetic radiation. Using an optical system of an optics arrangement, it is possible to receive the first electro-magnetic radiation(s), and modifying the at least one first electro-magnetic radiation to be at least one second electro-magnetic radiation so as to be forwarded to the sample. Further, with the optical system, it is possible to extend the at least one second electro-magnetic radiation into or across the sample for ...

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    3. 3D cellular-resolution imaging in arteries using few-mode interferometry

      3D cellular-resolution imaging in arteries using few-mode interferometry

      Article Open Access Published: 21 November 2019 3D cellular-resolution imaging in arteries using few-mode interferometry Biwei Yin , Zhonglie Piao , Kensuke Nishimiya , Chulho Hyun , Joseph A. Gardecki , Adam Mauskapf , Farouc A. Jaffer & Guillermo J. Tearney Light: Science & Applications volume 8 , Article number: 104 ( 2019 ) Cite this article Article metrics 3 Altmetric Metrics details Abstract Cross-sectional visualisation of the cellular and subcellular structures of human atherosclerosis in vivo is significant, as this disease is fundamentally caused by abnormal processes that occur at this scale in a depth-dependent manner. However, due to the inherent resolution-depth of focus tradeoff of conventional focusing optics, today ...

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    4. Cellular-resolution, extended depth of focus optical coherence tomography catheter toward in vivo cardiovascular imaging

      Cellular-resolution, extended depth of focus optical coherence tomography catheter toward in vivo cardiovascular imaging

      Optical coherence tomography (OCT) has been a useful clinical tool for diagnosing coronary artery disease through a flexible catheter, but its full promise relies on resolving cellular and sub-cellular structures in vivo. Previously, visualizing cellular structures through an imaging catheter is not possible due to limited depth of focus (DOF) of a tightly focused Gaussian beam: typically, a Gaussian beam with 2-3 μm resolution has a DOF within 100 μm, which is not sufficient for in vivo catheter imaging. Therefore, we developed a self-imaging wavefront division optical system that generates a coaxially-focused multimode (CAFM) beam with a DOF that is ...

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    5. Extended depth of focus for coherence-based cellular imaging

      Extended depth of focus for coherence-based cellular imaging

      Improving lateral resolution for cross-sectional optical coherence tomography (OCT) imaging is difficult due to the rapid divergence of light once it is focused to a small spot. To overcome this obstacle, we introduce a fiber optics system that generates a coaxially focused multimode (CAFM) beam for depth of focus (DOF) extension. We fabricated a CAFM beam OCT probe and show that the DOF is more than fivefold that of a conventional Gaussian beam, enabling cross-sectional imaging of biological tissues with clearly resolved cellular and subcellular structures over more than a 400 μm depth range. The compact and straightforward design and ...

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    6. Flexible, high-resolution micro-optical coherence tomography endobronchial probe toward in vivo imaging of cilia

      Flexible, high-resolution micro-optical coherence tomography endobronchial probe toward in vivo imaging of cilia

      We report the design and fabrication of a flexible, longitudinally scanning high-resolution micro-optical coherence tomography (μOCT) endobronchial probe, optimized for micro-anatomical imaging in airways. The 2.4 mm diameter and flexibility of the probe allows it to be inserted into the instrument channel of a standard bronchoscope, enabling real-time video guidance of probe placement. To generate a depth-of-focus enhancing annular beam, we utilized a new fabrication method, whereby a hollow glass ferrule was angle-polished and gold-coated to produce an elongated annular reflector. We present validation data that verifies the preservation of linear scanning, despite the use of flexible materials. When ...

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    7. Feature of the Week 04/24/2016: μOCT Imaging Using Depth of Focus Extension by Self-Imaging Wavefront Division in a Common-Path Fiber Optic Probe

      Feature of the Week 04/24/2016: μOCT Imaging Using Depth of Focus Extension by Self-Imaging Wavefront Division in a Common-Path Fiber Optic Probe

      Optical coherence tomography (OCT) is an attractive medical modality due to its ability to acquire high-resolution, cross-sectional images inside the body using flexible, small-diameter, scanning fiber optic probes. Conventional, cross-sectional OCT imaging technologies have approximately 10-μm axial resolution and 30-μm lateral resolution, specifications that enable the visualization of microscopic architectural morphology. While this resolution is useful for many clinical applications, it is insufficient for resolving individual cells that characterize many diseases. To address this gap, a supercontinuum-laser-based, μm-resolution OCT (μOCT) system and a 500 μm-diameter, extended depth of focus single fiber optic probe for endoscopic and intravascular imaging ...

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    8. μOCT imaging using depth of focus extension by self-imaging wavefront division in a common-path fiber optic probe

      μOCT imaging using depth of focus extension by self-imaging wavefront division in a common-path fiber optic probe

      Optical coherence tomography (OCT) is an attractive medical modality due to its ability to acquire high-resolution, cross-sectional images inside the body using flexible, small-diameter, scanning fiber optic probes. Conventional, cross-sectional OCT imaging technologies have approximately 10-μm axial resolution and 30-μm lateral resolution, specifications that enable the visualization of microscopic architectural morphology. While this resolution is useful for many clinical applications, it is insufficient for resolving individual cells that characterize many diseases. To address this gap, a supercontinuum-laser-based, μm-resolution OCT (μOCT) system and a 500 μm-diameter, extended depth of focus single fiber optic probe for endoscopic and intravascular imaging ...

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    9. Fourier optics analysis of phase-mask-based path-length-multiplexed optical coherence tomography

      Fourier optics analysis of phase-mask-based path-length-multiplexed optical coherence tomography

      Imaging below fingertip surface might be a useful alternative to the traditional fingerprint sensing since the internal finger features are more reliable than the external ones. One of the most promising subsurface imaging technique is optical coherence tomography (OCT), which, however, has to acquire 3-D data even when a single en face image is required. This makes OCT inherently slow for en face imaging and produce unnecessary large data sets. Here we demonstrate that full-field optical coherence tomography (FF-OCT) can be used to produce en face images of sweat pores and internal fingerprints, which can be used for the identification ...

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    10. Detection of plaque structure and composition using OCT combined with two-photon luminescence (TPL) imaging

      Detection of plaque structure and composition using OCT combined with two-photon luminescence (TPL) imaging

      Background and Objectives Atherosclerosis and plaque rupture leads to myocardial infarction and stroke. A novel hybrid optical coherence tomography (OCT) and two-photon luminescence (TPL) fiber-based imaging system was developed to characterize tissue constituents in the context of plaque morphology. Study Design/Materials and Methods Ex vivo coronary arteries (34 regions of interest) from three human hearts with atherosclerotic plaques were examined by OCT–TPL imaging. Histological sections (4 μm in thickness) were stained with Oil Red O for lipid, Von Kossa for calcium, and Verhoeff–Masson Tri-Elastic for collagen/elastin fibers and compared with imaging results. Results Biochemical components in ...

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    11. Degradation in the degree of polarization in human retinal nerve fiber layer

      Degradation in the degree of polarization in human retinal nerve fiber layer

      Using a fiber-based swept-source (SS) polarization-sensitive optical coherence tomography (PS-OCT) system, we investigate the degree of polarization (DOP) of light backscattered from the retinal nerve fiber layer (RNFL) in normal human subjects. Algorithms for processing data were developed to analyze the deviation in phase retardation and intensity of backscattered light in directions parallel and perpendicular to the nerve fiber axis (fast and slow axes of RNFL). Considering superior, inferior, and nasal quadrants, we observe the strongest degradation in the DOP with increasing RNFL depth in the temporal quadrant. Retinal ganglion cell axons in normal human subjects are known to have ...

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    12. Path-length-multiplexed scattering-angle-diverse optical coherence tomography for retinal imaging

      Path-length-multiplexed scattering-angle-diverse optical coherence tomography for retinal imaging

      A low-resolution path-length-multiplexed scattering angle diverse optical coherence tomography (PM-SAD-OCT) is constructed to investigate the scattering properties of the retinal nerve fiber layer (RNFL). Low-resolution PM-SAD-OCT retinal images acquired from a healthy human subject show the variation of RNFL scattering properties at retinal locations around the optic nerve head. The results are consistent with known retinal ganglion cell neural anatomy and principles of light scattering. Application of PM-SAD-OCT may provide potentially valuable diagnostic information for clinical retinal imaging.

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    13. Feature Of The Week 5/26/2013: University of Texas at Austin Investigates Dual-Wavelength Photothermal OCT for Imaging Microvasculature Blood Oxygen Saturation

      Feature Of The Week 5/26/2013: University of Texas at Austin Investigates Dual-Wavelength Photothermal OCT for Imaging Microvasculature Blood Oxygen Saturation

      A swept-source dual-wavelength photothermal optical coherence tomography (DWP-OCT) is demonstrated for imaging and measurement of microvasculature oxygen saturation (SO2). DWP-OCT is capable of recording three-dimensional images of tissue and depth-resolved phase variation in response to photothermal excitations in two different wavelengths (770 and 800 nm). Two phantom microvessels with different inner-diameter size (50 and 300 μm) were constructed, porcine blood with various SO2 levels were prepared for the experiment. Phantom microvessels were imaged and blood SO2 levels measured using DWP-OCT are compared with values provided by a commercial oximeter. Propagation error analysis suggests DWP-OCT is feasible for measurement of blood ...

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    14. Dual-wavelength photothermal optical coherence tomography for imaging microvasculature blood oxygen saturation

      Dual-wavelength photothermal optical coherence tomography for imaging microvasculature blood oxygen saturation

      A swept-source dual-wavelength photothermal (DWP) optical coherence tomography (OCT) system is demonstrated for quantitative imaging of microvasculature oxygen saturation. DWP-OCT is capable of recording three-dimensional images of tissue and depth-resolved phase variation in response to photothermal excitation. A 1,064-nm OCT probe and 770-nm and 800-nm photothermal excitation beams are combined in a single-mode optical fiber to measure microvasculature hemoglobin oxygen saturation ( SO 2 ) levels in phantom blood vessels with a range of blood flow speeds (0 to 17     mm / s ). A 50- μ m-diameter blood vessel phantom is imaged, and SO 2 levels are measured using DWP-OCT and compared with ...

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    15. Dual-wavelength photothermal optical coherence tomography for blood oxygen saturation measurement

      Dual-wavelength photothermal optical coherence tomography for blood oxygen saturation measurement

      We report design and demonstration of a dual wavelength photothermal (DWP) optical coherence tomography (OCT) system for imaging of a phantom microvessel and measurement of hemoglobin oxygen saturation (SO 2 ) level. The DWP-OCT system contains a swept-source (SS) two-beam phase-sensitive (PhS) OCT system (1060 nm) and two intensity modulated photothermal excitation lasers (770 nm and 800 nm). The PhS-OCT probe beam (1060 nm) and photothermal excitation beams are combined into one single-mode optical fiber. A galvanometer based two-dimensional achromatic scanning system is designed to provide 14 μm lateral resolution for the PhS-OCT probe beam (1060 nm) and 13 μm lateral ...

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    16. High-speed polarization sensitive optical coherence tomography for retinal diagnostics

      High-speed polarization sensitive optical coherence tomography for retinal diagnostics

      We report design and construction of an FPGA-based high-speed swept-source polarization-sensitive optical coherence tomography (SS-PS-OCT) system for clinical retinal imaging. Clinical application of the SS-PS-OCT system is accurate measurement and display of thickness, phase retardation and birefringence maps of the retinal nerve fiber layer (RNFL) in human subjects for early detection of glaucoma. The FPGA-based SS-PS-OCT system provides three incident polarization states on the eye and uses a bulk-optic polarization sensitive balanced detection module to record two orthogonal interference fringe signals. Interference fringe signals and relative phase retardation between two orthogonal polarization states are used to obtain Stokes vectors of ...

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    17. Optimized retinal nerve fiber layer segmentation based on optical reflectivity and birefringence for polarization-sensitive optical coherence tomography

      Optimized retinal nerve fiber layer segmentation based on optical reflectivity and birefringence for polarization-sensitive optical coherence tomography

      Segmentation of the retinal nerve fiber layer (RNFL) from swept source polarization-sensitive optical coherence tomography (SS-PSOCT) images is required to determine RNFL thickness and calculate birefringence. Traditional RNFL segmentation methods based on image processing and boundary detection algorithms utilize only optical reflectivity contrast information, which is strongly affected by speckle noise. We present a novel approach to segment the retinal nerve fiber layer (RNFL) using SS-PSOCT images including both optical reflectivity and phase retardation information. The RNFL anterior boundary is detected based on optical reflectivity change due to refractive index difference between the vitreous and inner limiting membrane. The posterior ...

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    1-19 of 19
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    1. (19 articles) Biwei Yin
    2. (10 articles) University of Texas at Austin
    3. (10 articles) Thomas E. Milner
    4. (9 articles) Massachusetts General Hospital
    5. (9 articles) Harvard University
    6. (9 articles) Guillermo J. Tearney
    7. (3 articles) Roman V. Kuranov
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    Optimized retinal nerve fiber layer segmentation based on optical reflectivity and birefringence for polarization-sensitive optical coherence tomography High-speed polarization sensitive optical coherence tomography for retinal diagnostics Dual-wavelength photothermal optical coherence tomography for blood oxygen saturation measurement Dual-wavelength photothermal optical coherence tomography for imaging microvasculature blood oxygen saturation Feature Of The Week 5/26/2013: University of Texas at Austin Investigates Dual-Wavelength Photothermal OCT for Imaging Microvasculature Blood Oxygen Saturation Path-length-multiplexed scattering-angle-diverse optical coherence tomography for retinal imaging Fourier optics analysis of phase-mask-based path-length-multiplexed optical coherence tomography μOCT imaging using depth of focus extension by self-imaging wavefront division in a common-path fiber optic probe Feature of the Week 04/24/2016: μOCT Imaging Using Depth of Focus Extension by Self-Imaging Wavefront Division in a Common-Path Fiber Optic Probe Flexible, high-resolution micro-optical coherence tomography endobronchial probe toward in vivo imaging of cilia In vivo dynamic characterization of the human tympanic membrane using pneumatic optical coherence tomography Negative Vessel Remodeling in Stargardt Disease Quantified with Volume-Rendered Optical Coherence Tomography Angiography