1. Articles from John C. Allen

    1-4 of 4
    1. Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension

      Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension

      In humans, the longitudinal characterisation of early optic nerve head (ONH) damage in ocular hypertension (OHT) is difficult as patients with glaucoma usually have structural ONH damage at the time of diagnosis. Previous studies assessed glaucomatous ONH cupping by measuring the anterior lamina cribrosa depth (LCD) and minimal rim width (MRW) using optical coherence tomography (OCT). In this study, we induced OHT by repeated intracameral microbead injections in 16 cynomolgus primates (10 unilateral; 6 bilateral) and assessed the structural changes of the ONH longitudinally to observe early changes. Elevated intraocular pressure (IOP) in OHT eyes was maintained for 7 months ...

      Read Full Article
    2. Evaluation of meridional scans for angle closure assessment with anterior segment swept-source optical coherence tomography

      Evaluation of meridional scans for angle closure assessment with anterior segment swept-source optical coherence tomography

      Background/aims As swept-source optical coherence tomography (SS-OCT) simultaneously obtains 128 meridional scans, it is important to identify which scans are playing the main role in classifying gonioscopic angle closure to simplify the analysis. We aimed to evaluate the diagnostic performance of every meridional scan in its ability to detect gonioscopic angle closure. Methods Observational study with 2027 phakic subjects consecutively recruited from a community polyclinic. Gonioscopy and SS-OCT were performed. Gonioscopic angle closure was defined as non-visibility of the posterior trabecular meshwork in ≥180° of the angle, while SS-OCT was defined as iridotrabecular contact anterior to the scleral spur ...

      Read Full Article
    3. Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy

      Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy

      Background/aims Although being a more objective tool for assessment and follow-up of angle closure, reliability studies have reported a moderate diagnostic performance for anterior segment optical coherence tomography (OCT) technologies when comparing with gonioscopy as the reference standard. We aim to determine factors associated with diagnostic disagreement in angle closure when assessed by anterior segment swept source OCT (SS-OCT, CASIA SS-1000; Tomey, Nagoya, Japan) and gonioscopy. Methods Cross-sectional study. A total of 2027 phakic subjects aged ≥50 years, with no relevant previous ophthalmic history, were consecutively recruited from a community polyclinic in Singapore. Gonioscopy and SS-OCT (128 radial scans ...

      Read Full Article
    4. Comparison of scanning laser ophthalmoscopy and high-definition optical coherence tomography measurements of optic disc parameters

      Comparison of scanning laser ophthalmoscopy and high-definition optical coherence tomography measurements of optic disc parameters

      Objective To investigate the agreement between scanning laser ophthalmoscopy (Heidelberg retinal tomograph 3; HRT-3) and high-definition optical coherence tomography (HD–OCT) for measurements of optic nerve head (ONH) parameters. Methods As part of a population-based cross-sectional study, 913 consecutive Chinese subjects aged 40 years and older underwent HRT-3 and HD–OCT imaging of the ONH after pupillary dilation. Limits of agreement (LOA) derived from Bland–Altman analysis were calculated for ONH measurements. Results The mean age (±SD) of study participants was 54.2±7.2 years and 52.0% were men. The two instruments showed no difference in mean optic ...

      Read Full Article
    1-4 of 4
  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. (4 articles) Singapore Eye Research Institute
    2. (4 articles) Tin Aung
    3. (3 articles) National University of Singapore
    4. (2 articles) Mani Baskaran
    5. (1 articles) Massachusetts Eye and Ear Infirmary
    6. (1 articles) Duke University
    7. (1 articles) David S. Friedman
    8. (1 articles) Tien Yin Wong
    9. (1 articles) Tomey Corporation
    10. (1 articles) Heidelberg Engineering
  3. Popular Articles

  4. Picture Gallery

    Comparison of scanning laser ophthalmoscopy and high-definition optical coherence tomography measurements of optic disc parameters Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy Evaluation of meridional scans for angle closure assessment with anterior segment swept-source optical coherence tomography Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension Customized Slab-Segmentation Method for Projection-Artifact Elimination in Best Vitelliform Macular Dystrophy: A Swept-Source Optical Coherence Tomography Angiography Study Corneal Epithelial Thickness Profile in Healthy Portuguese Children by High-Definition Optical Coherence Tomography Prediction model for best focus, power, and spherical aberration of the cornea: Raytracing on a large dataset of OCT data Classification of pachychoroid on optical coherence tomography using deep learning Noninvasive Evaluation of HepaRG Aggregates during Drug‐Induced Intrahepatic Cholestasis Using Optical Coherence Tomography Online measurement of floc size, viscosity, and consistency of cellulose microfibril suspensions with optical coherence tomography A Joint Model for Macular Edema Analysis in Optical Coherence Tomography Images Based on Image Enhancement and Segmentation Choroidal Thickness by Handheld Swept-Source Optical Coherence Tomography in Term Newborns