1. Articles from Steven M. Jones

    1-13 of 13
    1. In-vivo imaging of inner retinal cellular morphology with adaptive optics-optical coherence tomography: challenges and possible solutions

      In-vivo imaging of inner retinal cellular morphology with adaptive optics-optical coherence tomography: challenges and possible solutions

      Recent progress in retinal image acquisition techniques, including optical coherence tomography (OCT) and scanning laser ophthalmoscopy (SLO), combined with improved performance of adaptive optics (AO) instrumentation, has resulted in improvement in the quality of in vivo images of cellular structures in the outer layers of the human retina. Despite the significant progress in imaging cone and rod photoreceptor mosaics, visualization of cellular structures in the inner retina has been achieved only with extrinsic contrast agents that have not been approved for use with humans. In this paper we describe the main limiting factors in visualizing inner retinal cells and the ...

      Read Full Article
    2. Performance of 97-elements ALPAO membrane magnetic deformable mirror in Adaptive Optics - Optical Coherence Tomography system for in vivo imaging of human retina

      Performance of 97-elements ALPAO membrane magnetic deformable mirror in Adaptive Optics - Optical Coherence Tomography system for in vivo imaging of human retina
      We present an evaluation of two different configurations of the ALPAO 97-actuator membrane magnetic deformable mirror for wavefront correction, using either 7 or 9 actuators across the eye pupil. These tests included monitoring of aberration correction for a human subject. This AO-sub system is part of the UC Davis high-resolution human retinal imaging adaptive optics - optical coherence tomography (AO-OCT) instrument. AO-OCT allows the three-dimensional (3D) visualization of different retinal structures in vivo with high volumetric resolution (3x3x3µm3). Full Text: PDF References: [1] R.J. Zawadzki, S. Jones, S. Olivier, M. Zhao, B. Bower, J. Izatt, S. Choi, S. Laut, and ...
      Read Full Article
    3. Integrated adaptive optics optical coherence tomography and adaptive optics scanning laser ophthalmoscope system for simultaneous cellular resolution in vivo retinal imaging

      Integrated adaptive optics optical coherence tomography and adaptive optics scanning laser ophthalmoscope system for simultaneous cellular resolution in vivo retinal imaging
      , , , , , , We describe an ultrahigh-resolution (UHR) retinal imaging system that combines adaptive optics Fourier-domain optical coherence tomography (AO-OCT) with an adaptive optics scanning laser ophthalmoscope (AO-SLO) to allow simultaneous data acquisition by the two modalities. The AO-SLO subsystem was ... [Biomed. Opt. Express 2, 1674-1686 (2011)]
      Read Full Article
    4. Compact adaptive optic-optical coherence tomography system

      Compact adaptive optic-optical coherence tomography system
      Badal Optometer and rotating cylinders are inserted in the AO-OCT to correct large spectacle aberrations such as myopia, hyperopic and astigmatism for ease of clinical use and reduction. Spherical mirrors in the sets of the telescope are rotated orthogonally to reduce aberrations and beam displacement caused by the scanners. This produces greatly reduced AO registration errors and improved AO performance to enable high order aberration correction in a patient eyes.
      Read Full Article
    5. AO-OCT with reference arm phase shifting for complex conjugate artifact-free imaging of in vivo retinal structures

      AO-OCT with reference arm phase shifting for complex conjugate artifact-free imaging of in vivo retinal structures

      We summarize the performance of an AO-OCT system with reference arm phase shifting for complex conjugate artifactfree imaging of in vivo retinal structures. As a complex conjugate artifact removal (CCR) method we used a previously reported technique requiring constant phase shifts between consecutive A-scans. In our system these shifts were generated by continuous beam path-length changes from offsetting the pivot point of the scanning mirror placed in the system reference arm. In order to reconstruct the complex spectral fringe pattern we used Fourier transformation along the transverse axis and a filtering algorithm. The suppression ratio of mirror complex artifact images ...

      Read Full Article
    6. High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography

      High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography
      This invention permits retinal images to be acquired at high speed and with unprecedented resolution in three dimensions (4.times.4.times.6 .mu.m). The instrument achieves high lateral resolution by using adaptive optics to correct optical aberrations of the human eye in real time. High axial resolution and high speed are made possible by the use of Fourier-domain optical coherence tomography. Using this system, we have demonstrated the ability to image microscopic blood vessels and the cone photoreceptor mosaic.
      Read Full Article
    7. Retinal imaging with a combined adaptive optics/optical coherence tomography and adaptive optics/scanning laser ophthalmoscopy system

      Retinal imaging with a combined adaptive optics/optical coherence tomography and adaptive optics/scanning laser ophthalmoscopy system
      We describe results of retinal imaging with a novel instrument that combines adaptive optics - Fourier-domain optical coherence tomography (AO-OCT) with an adaptive optics scanning laser ophthalmoscope (AO-SLO). One of the benefits of combining Fd-OCT with SLO includes automatic co-registration between the two imaging modalities and the potential for correcting lateral and transversal eye motion resulting in motion artifact-free volumetric retinal imaging. Additionally this allows for direct comparison between retinal structures that can be imaged with both modalities (e.g., photoreceptor mosaics or microvasculature maps). This dual imaging modality could provide insight into some retinal properties that could not be accessed ...
      Read Full Article
    8. Retinal imaging with polarization-sensitive optical coherence tomography and adaptive optics

      Retinal imaging with polarization-sensitive optical coherence tomography and adaptive optics

      Various layers of the retina are well known to alter the polarization state of light. Such changes in polarization may be a sensitive indicator of tissue structure and function, and as such have gained increased clinical attention. Here we demonstrate a polarization-sensitive optical coherence tomography (PS-OCT) system that incorporates adaptive optics (AO) in the sample arm and a single line scan camera in the detection arm. We quantify the benefit of AO for PS-OCT in terms of signal-to-noise, lateral resolution, and speckle size. Double pass phase retardation per unit depth values ranging from 0.25°/μm to 0.65°/μm ...

      Read Full Article
    9. Error Budget Analysis for an Adaptive Optics Optical Coherence Tomography System

      Error Budget Analysis for an Adaptive Optics Optical Coherence Tomography System
      The combination of adaptive optics (AO) technology with optical coherence tomography (OCT) instrumentation for imaging the retina has proven to be a valuable tool for clinicians and researchers in understanding the healthy and diseased eye. The micrometer-isotropic resolution achieved by such a system allows imaging of the retina at a cellular level, however imaging of some cell types remains elusive. Improvement in contrast rather than resolution is needed and can be achieved through better AO correction of wavefront aberration. A common tool for assessing and ultimately improving AO system performance is the development of an error budget. Specifically, this is ...
      Read Full Article
    10. Combined adaptive optics: optical coherence tomography and adaptive optics: scanning laser ophthalmoscopy system for retinal imaging

      We describe a novel instrument that combines adaptive optics - Fourier-domain optical coherence tomography (AO-OCT) with an adaptive optics scanning laser ophthalmoscope (AO-SLO). Both systems share a common AO sub-system and vertical scanner to permit simultaneous acquisition of retinal images from ... [Proc. SPIE 7163, 71630F (2009)] published Wed Feb 18, 2009.
      Read Full Article
    11. Ultra-high resolution adaptive optics: optical coherence tomography for in vivo imaging of healthy and diseased retinal structures

      Ultra-high isotropic resolution imaging of retinal structures was made possible with an adaptive optics system using dual deformable mirrors and a Fourier-domain optical coherence tomography (Fd-OCT) system with correction for longitudinal chromatic aberration. This system was used to image microsco ... [Proc. SPIE Int. Soc. Opt. Eng. 6844, 684408 (2008)] published Mon Feb 11, 2008.
      Read Full Article
    12. Compact MEMS-based adaptive optics: optical coherence tomography for clinical use

      We describe a compact MEMS-based adaptive optics (AO) optical coherence tomography (OCT) system with improved AO performance and ease of clinical use. A typical AO system consists of a Shack-Hartmann wavefront sensor and a deformable mirror that measures and corrects the ocular and system aberrations. Because of limitations on current deformable mirror technologies, the amount of real-time ocular-aberration compensation is restricted and small in previous AO-OCT instruments. In this instrument, we incorporate an optical apparatus to correct the spectacle aberrations of the patients such as myopia, hyperopia and astigmatism. This eliminates the tedious process of using trial lenses in clinical ...
      Read Full Article
    1-13 of 13
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Topics in the News

    1. (13 articles) Steven M. Jones
    2. (12 articles) Lawrence Livermore National Laboratory
    3. (12 articles) Scot S. Olivier
    4. (11 articles) John S. Werner
    5. (11 articles) Robert J. Zawadzki
    6. (10 articles) UC Davis
    7. (5 articles) Julia W. Evans
    8. (4 articles) Dae Yu Kim
    9. (3 articles) Indiana University
    10. (3 articles) Barry Cense
    11. (1 articles) Medical University of Vienna
    12. (1 articles) Harvard University
    13. (1 articles) NYU Langone Medical Center
    14. (1 articles) Massachusetts General Hospital
    15. (1 articles) Tianjin University
    16. (1 articles) University of Hong Kong
    17. (1 articles) Semmelweis University
    18. (1 articles) Guillermo J. Tearney
    19. (1 articles) Arnaud Dubois
    20. (1 articles) Ursula Schmidt-Erfurth
  3. Popular Articles

  4. Picture Gallery

    Ultra-high-resolution optical coherence tomography gets adaptive-optic ‘glasses’ Error Budget Analysis for an Adaptive Optics Optical Coherence Tomography System Retinal imaging with polarization-sensitive optical coherence tomography and adaptive optics Retinal imaging with a combined adaptive optics/optical coherence tomography and adaptive optics/scanning laser ophthalmoscopy system High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography AO-OCT with reference arm phase shifting for complex conjugate artifact-free imaging of in vivo retinal structures Integrated adaptive optics optical coherence tomography and adaptive optics scanning laser ophthalmoscope system for simultaneous cellular resolution in vivo retinal imaging Performance of 97-elements ALPAO membrane magnetic deformable mirror in Adaptive Optics - Optical Coherence Tomography system for in vivo imaging of human retina Selective retinex enhancement based on the clustering algorithm and block-matching 3D for optical coherence tomography images Artificial intelligence, the internet of things, and virtual clinics: ophthalmology at the digital translation forefront Detecting glaucoma based on spectral domain optical coherence tomography imaging of peripapillary retinal nerve fiber layer: a comparison study between hand-crafted features and deep learning model Comparison of line‐field confocal optical coherence tomography images with histological sections: Validation of a new method for in vivo and non‐invasive quantification of superficial dermis thickness