July 2019
Volume 60, Issue 9
Free
ARVO Annual Meeting Abstract  |   July 2019
Response Reliability during Automated Visual Photosensitivity Assessment in Achromatopsia
Author Affiliations & Notes
  • Alex Gonzalez
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Mariela Aguilar
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Cornelis Rowaan
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Potyra R. Rosa
    Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Victoria M. Graham
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Barry E. Hurwitz
    Behavioral Medicine Research Center, Psychology, University of Miami, Miami, Florida, United States
  • Byron L Lam
    Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
  • Jean-Marie Parel
    Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States
    Brien Holden Vision Institute, University of New South Wales, New South Wales, Australia
  • Footnotes
    Commercial Relationships   Alex Gonzalez, None; Mariela Aguilar, None; Cornelis Rowaan, None; Potyra Rosa, None; Victoria Graham, None; Barry Hurwitz, None; Byron Lam, None; Jean-Marie Parel, None
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science July 2019, Vol.60, 5934. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Alex Gonzalez, Mariela Aguilar, Cornelis Rowaan, Potyra R. Rosa, Victoria M. Graham, Barry E. Hurwitz, Byron L Lam, Jean-Marie Parel; Response Reliability during Automated Visual Photosensitivity Assessment in Achromatopsia. Invest. Ophthalmol. Vis. Sci. 2019;60(9):5934.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : The Ocular Photosensitivity Analyzer (OPA, Fig. 1, Aguilar et al. BOE 2018,9(11):5583-5596) is an automated instrument designed to quantify visual photosensitivity thresholds (VPT) to light stimuli while incorporating catch trials throughout the test as an index of response reliability. A catch trial is defined as a repetition of a randomly-selected previously presented light stimulus. The response to a light stimulus is compared to the response of a subsequent catch trial stimulus for agreement. This study examined the differences in catch trial agreement between healthy subjects and subjects with achromatopsia (rod monochromatism), a retinal genetic disorder characterized by severe light sensitivity.

Methods : From 2014-2018, 278 OPA tests have been conducted on 16 subjects with genetic proven CNGB3 or CNGA3 achromatopsia (age 7 to 57 years) and 35 healthy subjects (age 8 to 61 years). Monocular and binocular (OD, OS, & OU) VPT measurements were obtained at two time points. Exam room lighting was adjusted to 4 lux, while subjects rested for 10 minutes. Synthesized speech audio test instructions were provided and subjects were instructed to indicate when a light stimulus was uncomfortable by pressing a push-button. The VPT was calculated from the mean of 10 response reversals (Fig. 2). Every third light stimulus is a catch trial presented to the subject at the same intensity as a previously presented stimulus.

Results : The VPT of the achromatopsia subjects was significantly lower than in the healthy subjects (0.74 ± 0.55 log Lux vs. 2.18 ± 0.83 log Lux, respectively; p<.001). Notably, poorer response agreement was observed in the achromatopsia subjects than in the healthy subjects (p<.001). Catch trial agreement for the healthy subjects was 81.0 ± 0.2% compared with 70.1 ± 0.2% for the achromatopsia subjects. VPT was significantly associated with catch trial agreement (r=0.241, p<.001).

Conclusions : Achromatopsia subjects demonstrated diminished light sensitivity response reliability compared with healthy subjects. With repeated test trials as used in psychophysical thresholding methodology, greater variability of light sensitivity response agreement may be expected in subjects with impaired visual photosensitivity depending on disease severity. Our findings have implications in the use of the OPA as an outcome measure in achromatopsia clinical trials.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

 

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×