Blog
About

  • Record: found
  • Abstract: found
  • Article: found
Is Open Access

Impact of image quality on OCT angiography based quantitative measurements

Read this article at

Bookmark
      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

      Abstract

      BackgroundTo study the impact of image quality on quantitative measurements and the frequency of segmentation error with optical coherence tomography angiography (OCTA).MethodsSeventeen eyes of 10 healthy individuals were included in this study. OCTA was performed using a swept-source device (Triton, Topcon). Each subject underwent three scanning sessions 1–2 min apart; the first two scans were obtained under standard conditions and for the third session, the image quality index was reduced using application of a topical ointment. En face OCTA images of the retinal vasculature were generated using the default segmentation for the superficial and deep retinal layer (SRL, DRL). Intraclass correlation coefficient (ICC) was used as a measure for repeatability. The frequency of segmentation error, motion artifact, banding artifact and projection artifact was also compared among the three sessions.ResultsThe frequency of segmentation error, and motion artifact was statistically similar between high and low image quality sessions (P = 0.707, and P = 1 respectively). However, the frequency of projection and banding artifact was higher with a lower image quality. The vessel density in the SRL was highly repeatable in the high image quality sessions (ICC = 0.8), however, the repeatability was low, comparing the high and low image quality measurements (ICC = 0.3). In the DRL, the repeatability of the vessel density measurements was fair in the high quality sessions (ICC = 0.6 and ICC = 0.5, with and without automatic artifact removal, respectively) and poor comparing high and low image quality sessions (ICC = 0.3 and ICC = 0.06, with and without automatic artifact removal, respectively).ConclusionsThe frequency of artifacts is higher and the repeatability of the measurements is lower with lower image quality. The impact of image quality index should be always considered in OCTA based quantitative measurements.

      Related collections

      Most cited references 27

      • Record: found
      • Abstract: found
      • Article: not found

      NIH Image to ImageJ: 25 years of image analysis.

      For the past 25 years NIH Image and ImageJ software have been pioneers as open tools for the analysis of scientific images. We discuss the origins, challenges and solutions of these two programs, and how their history can serve to advise and inform other software projects.
        Bookmark
        • Record: found
        • Abstract: found
        • Article: found
        Is Open Access

        Split-spectrum amplitude-decorrelation angiography with optical coherence tomography

        Amplitude decorrelation measurement is sensitive to transverse flow and immune to phase noise in comparison to Doppler and other phase-based approaches. However, the high axial resolution of OCT makes it very sensitive to the pulsatile bulk motion noise in the axial direction. To overcome this limitation, we developed split-spectrum amplitude-decorrelation angiography (SSADA) to improve the signal-to-noise ratio (SNR) of flow detection. The full OCT spectrum was split into several narrower bands. Inter-B-scan decorrelation was computed using the spectral bands separately and then averaged. The SSADA algorithm was tested on in vivo images of the human macula and optic nerve head. It significantly improved both SNR for flow detection and connectivity of microvascular network when compared to other amplitude-decorrelation algorithms.
          Bookmark
          • Record: found
          • Abstract: found
          • Article: not found

          Retinal vascular layers imaged by fluorescein angiography and optical coherence tomography angiography.

          The retinal vasculature is involved in many ocular diseases that cause visual loss. Although fluorescein angiography is the criterion standard for evaluating the retina vasculature, it has risks of adverse effects and known defects in imaging all the layers of the retinal vasculature. Optical coherence tomography (OCT) angiography can image vessels based on flow characteristics and may provide improved information.
            Bookmark

            Author and article information

            Affiliations
            [1 ]ISNI 0000 0001 0097 5623, GRID grid.280881.b, Doheny Image Reading Center, , Doheny Eye Institute, ; Los Angeles, CA USA
            [2 ]ISNI 0000 0000 9632 6718, GRID grid.19006.3e, Department of Ophthalmology, David Geffen School of Medicine, , University of California – Los Angeles, ; Los Angeles, CA USA
            [3 ]ISNI 0000 0004 1937 0650, GRID grid.7400.3, Department of Ophthalmology, University Hospital Zurich, , University of Zurich, ; Zurich, Switzerland
            [4 ]GRID grid.411746.1, Eye Research Center, Rassoul Akram Hospital, , Iran University of Medical Sciences, ; Tehran, Iran
            Contributors
            mayss.alsheikh@gmail.com
            drghasemi@yahoo.com
            hakil@doheny.org
            ssadda@doheny.org
            Journal
            Int J Retina Vitreous
            Int J Retina Vitreous
            International Journal of Retina and Vitreous
            BioMed Central (London )
            2056-9920
            15 May 2017
            15 May 2017
            2017
            : 3
            5430594
            68
            10.1186/s40942-017-0068-9
            © The Author(s) 2017

            Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

            Categories
            Original Article
            Custom metadata
            © The Author(s) 2017

            Comments

            Comment on this article