1. Articles from Paul Fieguth

    1-5 of 5
    1. Noise-compensated Homotopic Non-local Regularized Reconstruction for Rapid Retinal Optical Coherence Tomography Image Acquisitions

      Noise-compensated Homotopic Non-local Regularized Reconstruction for Rapid Retinal Optical Coherence Tomography Image Acquisitions

      Background Optical coherence tomography (OCT) is a minimally invasive imaging technique, which utilizes the spatial and temporal coherence properties of optical waves backscattered from biological material. Recent advances in tunable lasers and infrared camera technologies have enabled an increase in the OCT imaging speed by a factor of more than 100, which is important for retinal imaging where we wish to study fast physiological processes in the biological tissue. However, the high scanning rate causes proportional decrease of the detector exposure time, resulting in a reduction of the system signal-to-noise ratio (SNR). One approach to improving the image quality of ...

      Read Full Article
    2. Automatic tracking of pupillary dynamics from in vivo functional optical coherence tomography images

      Automatic tracking of pupillary dynamics from in vivo functional optical coherence tomography images

      A major challenge currently faced in measuring visually evoked optical changes in different retinal layers using in vivo and non-invasive functional optical coherence tomography (fOCT) is the need for pupillary dilation drugs to enable reliable measurement of the retinal functional responses. However, there are situations where the use of pupillary dilation drugs is not suitable in both clinical and animal ophthalmic research situations. To overcome this challenge, we propose a new approach to tracking visually evoked pupillary dynamics, based on the use of a fast scanning fOCT system and a novel computerised framework, which can then be used to isolate ...

      Read Full Article
    3. Energy-guided learning approach to compressive FD-OCT

      Energy-guided learning approach to compressive FD-OCT

      High quality, large size volumetric imaging of biological tissue with optical coherence tomography (OCT) requires large number and high density of scans, which results in large data acquisition volume. This may lead to corruption of the data with motion artifacts related to natural motion of biological tissue, and could potentially cause conflicts with the maximum permissible exposure of biological tissue to optical radiation. Therefore, OCT can benefit greatly from different approaches to sparse or compressive sampling of the data where the signal is recovered from its sub-Nyquist measurements. In this paper, a new energy-guided compressive sensing approach is proposed for ...

      Read Full Article
    4. Homotopic, non-local sparse reconstruction of optical coherence tomography imagery

      Homotopic, non-local sparse reconstruction of optical coherence tomography imagery

      The resolution in optical coherence tomography imaging is an important parameter which determines the size of the smallest features that can be visualized. Sparse sampling approaches have shown considerable promise in producing high resolution OCT images with fewer camera pixels, reducing both the cost and the complexity of an imaging system. In this paper, we propose a non-local approach to the reconstruction of high resolution OCT images from sparsely sampled measurements. An iterative strategy is introduced for minimizing a homotopic, non-local regularized functional in the spatial domain, subject to data fidelity constraints in the k-space domain. The novel algorithm was ...

      Read Full Article
    5. Evaluation of hypoxic swelling of human cornea with high speed, ultrahigh resolution optical coherence tomography

      Hypoxia induced corneal swelling was observed and evaluated in healthy human volunteers by use of high speed, ultrahigh resolution optical coherence tomography (UHROCT). Two dimensional corneal images were acquired at a speed of 47,000 A-scans/s with 3m x 10m (axial x lateral) resolution in corneal tissue. The UHROCT tomograms showed clear visualization of all corneal layers, including the Bowman's layer and the Descemet's membrane - Endothelium complex. A segmentation algorithm was developed and used for automatic detection of the boundaries of the different corneal layers and evaluation the individual layer thickness as a function of location. Corneal ...

      Read Full Article
    1-5 of 5
  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. (5 articles) University of Waterloo
    2. (5 articles) Kostadinka K. Bizheva
    3. (1 articles) Natalie Hutchings
    4. (1 articles) Sepideh Hariri
    5. (1 articles) Alireza A. Moayed
    6. (1 articles) Samsung
    7. (1 articles) Johns Hopkins University
    8. (1 articles) National Institutes of Health
    9. (1 articles) Sungkyunkwan University
    10. (1 articles) University of São Paulo
    11. (1 articles) Massachusetts Institute of Technology
    12. (1 articles) L V Prasad Eye Institute
    13. (1 articles) Gong Je Seong
    14. (1 articles) Chan Yun Kim
    15. (1 articles) James G. Fujimoto
  3. Popular Articles

  4. Picture Gallery

    Homotopic, non-local sparse reconstruction of optical coherence tomography imagery Energy-guided learning approach to compressive FD-OCT Automatic tracking of pupillary dynamics from in vivo functional optical coherence tomography images Noise-compensated Homotopic Non-local Regularized Reconstruction for Rapid Retinal Optical Coherence Tomography Image Acquisitions Factors Associated with Changes in Retinal Layers Following Acute Optic Neuritis: A Longitudinal Study Using Optical Coherence Tomography Relationship between N95 Amplitude of Pattern Electroretinogram and Optical Coherence Tomography Angiography in Open-Angle Glaucoma Historic Effort to 'End Blindness" Marks a Major Milestone with Leading Scientist Recognized for Pioneering Work at VIP Ceremony Featuring Tribute to Ruth Bader Ginsburg Healing and early stent coverage after ultrathin strut biodegradable polymer‐coated sirolimus‐eluting stent implantation: SiBi optical coherence tomography study Influences of hypomagnesemia on optic nerve and retinal vascular structure determined using optical coherence tomography angiography Repeatability and agreement of total corneal and sublayer pachymetry with 2 different algorithms of Fourier-domain optical coherence tomography in myopic and postphotorefractive keratectomy eyes Vessel Density around Foveal Avascular Zone as a Potential Imaging Biomarker for Detecting Preclinical Diabetic Retinopathy: An Optical Coherence Tomography Angiography Study Vascular risk factors for optical coherence tomography-detected macular cysts: The Maastricht Study