1. Articles from J. Stuart Nelson

    1-10 of 10
    1. In vivo, high-resolution, three-dimensional imaging of port wine stain microvasculature in human skin

      In vivo, high-resolution, three-dimensional imaging of port wine stain microvasculature in human skin

      Port-wine stain (PWS) is a congenital, progressive vascular malformation of the dermis. In the past few years, advances in optical coherence tomography (OCT) technology have greatly increased imaging speed. Sophisticated numerical algorithms have improved the sensitivity of Doppler OCT dramatically. These improvements have enabled the noninvasive, high-resolution, three-dimensional functional imaging of PWS skin. In this study, high-resolution, three-dimensional, microvasculature imaging of PWS using Doppler OCT technique is demonstrated. Three-dimensional imaging of the subsurface vessel network of the dermis can provide information for accurate PWS classification and guidance for effective laser treatment. Invasive methods such as histology following biopsy and confocal ...

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    2. In vivo, high-resolution, three-dimensional imaging of port wine stain microvasculature in human skin

      In vivo, high-resolution, three-dimensional imaging of port wine stain microvasculature in human skin

      Background and Objectives Port-wine stain (PWS) is a congenital, progressive vascular malformation of the dermis. The use of optical coherence tomography (OCT) for the characterization of blood vessels in PWS skin has been demonstrated by several groups. In the past few years, advances in OCT technology have greatly increased imaging speed. Sophisticated numerical algorithms have improved the sensitivity of Doppler OCT dramatically. These improvements have enabled the noninvasive, high-resolution, three-dimensional functional imaging of PWS skin. Here, we demonstrate high-resolution, three-dimensional, microvasculature imaging of PWS and normal skin using Doppler OCT technique. Study Design/Materials and Methods The OCT system uses ...

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    3. Systems, devices, and methods for optically clearing tissue

      Systems, devices, and methods for optically clearing tissue

      Embodiments of the present disclosure provides systems, devices, and methods for non-invasively modifying, maintaining, or controlling local tissue optical properties. Methods and devices of the disclosure may be used for optically clearing tissue, for example, for diagnostic and/or therapeutic purposes. A method of optically clearing a tissue may comprise contacting the tissue with an optical clearing device having a base, an array of pins fixed to one side of the base, a brim fixed to the base, an inlet port in the base, an exit port in the base, and a handpiece interface tab fixed to the side of ...

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    4. Spectral Doppler imaging of micro-vasculature response to laser irradiation

      Doppler Optical Coherence Tomography (DOCT) imaging of in-vivo retinal blood flow was widely studied as efforts of research community to push this technology into clinic. Spectral Doppler imaging of DOCT has been demonstrated as a quantification method of in-vivo pulsatile retinal blood flow in human eye. This technology has the all the advantages inherited from OCT comparing to Doppler ultrasound. Comparing to normal spatial-distributed color Doppler imaging of DOCT, spectral Doppler imaging can reveal more haemodynamics details on the time dimension. Although resistance index (RI) of a micro-vascular can be measured in vivo from human retina, the clinical significance of ...
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    5. High speed spectral domain functional optical coherence tomography and optical doppler tomography for in vivo blood flow dynamics and tissue structure

      A system for tomographic imaging includes a source of at least partially coherent radiation, a frequency-swept laser source and an interferometer. The radiation in the interferometer is phase modulated at a modulation frequency for elimination of DC and autocorrelation noises as well as the mirror image. The interference fringes of the radiation backscattered from the sample into the interferometer are detected to obtain a spectral signal. The spectral signal of the detected backscattered interference fringes is transformed to obtain a location dependent signal at each pixel location in a data window. A tomographic image of the fluid flow in the ...
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    6. High resolution optical coherence tomography with an improved depth range using an axicon lens

      In optical coherence tomography (OCT), Axial and lateral resolutions are determined by the source coherence length and numerical aperture of the sampling lens, respectively. While axial resolution can be improved using a broadband light source, there is a trade-off between lateral resolution and focusing depth when conventional optical elements are used. The incorporation of an axicon lens into the sample arm of the interferometer overcomes this limitation. Using an axicon lens with a top angle of 160 degrees, 10 .mu.m or better-lateral resolution is maintained over a focusing depth of at least 6 mm. In addition to high lateral ...

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    7. Phase-resolved functional optical coherence tomography: simultaneous imaging of the stokes vectors, structure, blood flow velocity, standard deviation and birefringence in biological samples

      A phase-resolved functional optical coherence tomography system simultaneously obtains the Stokes vectors, structure, blood flow velocity, standard deviation, and birefringence images in human skin. The multifunctional images were obtained by processing the analytical interference fringe signals derived from the two perpendicular polarization detection channels. The blood flow velocity and standard deviation images were obtained by comparing the phase from the pairs of analytical signals in the neighboring A-lines in the same polarization state. The Stokes vectors were obtained by processing the analytical signals from two polarization diversity detection channels for the same reference polarization state. From the four Stokes vectors ...
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    8. Imaging transverse flow velocity using spectral bandwidth of the doppler frequency shift in phase-resolved optical doppler tomography

      The Doppler bandwidth extracted from the standard deviation of the frequency shift in phase-resolved optical Doppler tomography (ODT) is used to image the velocity component transverse to the probing beam. The effective numerical aperture (NA) of the optical objective determines the slope of the dependence of the standard deviation on velocity. In the case where the angle between the probing beam and flow direction is within .+-.15 degrees to the perpendicular, the Doppler frequency shift is very sensitive to angle position while the Doppler bandwidth is insensitive to flow direction. Linear dependence of the flow velocity on the Doppler bandwidth ...
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    9. Phase-resolved optical coherence tomography and optical doppler tomography for imaging fluid flow in tissue with fast scanning speed and high velocity sensitivity

      The invention is a fast-scanning ODT system that uses phase information derived from a Hilbert transformation to increase the sensitivity of flow velocity measurements while maintaining high spatial resolution. The significant increases in scanning speed and velocity sensitivity realized by the invention make it possible to image in vivo blood flow in human skin. The method of the invention overcomes the inherent limitations of the prior art ODT by using a phase change between sequential line scans for velocity image reconstruction. The ODT signal phase or phase shifts at each pixel can be determined from the complex function, .GAMMA..sub ...
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    10. Birefringence imaging in biological tissue using polarization sensitive optical coherent tomography

      Employing a low coherence Michelson interferometer, two dimensional images of optical birefringence in turbid samples as a function of depth are measured. Polarization sensitive detection of the signal formed by interference of backscattered light from the sample and a mirror or reference plane in the reference arm which defines a reference optical path length, give the optical phase delay between light propagating along the fast and slow axes of the birefringence sample. Images showing the change in birefringence in response to irradiation of the sample are produced as an example of the detection apparatus and methodology. The technique allow rapid ...
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    1-10 of 10
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  2. Topics in the News

    1. (10 articles) J. Stuart Nelson
    2. (8 articles) Zhongping Chen
    3. (7 articles) UC Irvine
    4. (2 articles) Thomas E. Milner
    5. (2 articles) Johannes F. de Boer
    6. (2 articles) Gangjun Liu
    7. (2 articles) Cambridge Technology
    8. (2 articles) Columbia University
    9. (2 articles) Christine P. Hendon
    10. (2 articles) Canon Medical Systems
    11. (1 articles) Zhihua Ding
    12. (1 articles) Bernard Choi
    13. (1 articles) Lingfeng Yu
    14. (1 articles) University of Houston
    15. (1 articles) Kyoto University Graduate School of Medicine
    16. (1 articles) Dmitry A. Terpelov
    17. (1 articles) David D. Sampson
    18. (1 articles) Eric A. Swanson
    19. (1 articles) Akitaka Tsujikawa
    20. (1 articles) Kirill V. Larin
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