September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
Natural History of Rod-Mediated Dark Adaptation Over 2 Years in Eyes with Intermediate Age-Related Macular Degeneration
Author Affiliations & Notes
  • Cynthia Owsley
    Dept of Ophthalmology, University of Alabama at Birmingham, Birmingham, Alabama, United States
  • Mark Clark
    Dept of Ophthalmology, University of Alabama at Birmingham, Birmingham, Alabama, United States
  • Gerald McGwin
    Epidemiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
    Dept of Ophthalmology, University of Alabama at Birmingham, Birmingham, Alabama, United States
  • Eric C Strauss
    Genentech, South San Francisco, California, United States
  • Footnotes
    Commercial Relationships   Cynthia Owsley, Genentech (F), University of Alabama at Birmingham (P); Mark Clark, None; Gerald McGwin, None; Eric Strauss, Genentech (E), Genentech (I)
  • Footnotes
    Support  Genentech, Research to Prevent Blindness, NIH R01AG04212, EyeSight Foundation of Alabama
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 3690. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Cynthia Owsley, Mark Clark, Gerald McGwin, Eric C Strauss; Natural History of Rod-Mediated Dark Adaptation Over 2 Years in Eyes with Intermediate Age-Related Macular Degeneration. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3690.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : How does rod-mediated dark adaptation (RMDA) change over time in eyes with intermediate age-related macular degeneration (AMD)? This information will be useful in assessing the candidacy of RMDA as a potential outcome in evaluating interventions to prevent advanced AMD or to arrest its progression.

Methods : Inclusion criteria were persons ≥50 yo with at least 1 eye with intermediate AMD (multiple large confluent drusen area ≥0.5 disk area, with or without increased or decreased RPE pigmentation), designated as the study eye; fellow eye with intermediate AMD, geographic atrophy or choroidal neovascularization; BCVA in study eye of 20/100 or better. AMD presence was determined by evaluation of color fundus photographs by a masked, trained grader. RMDA was assessed in the study eye at baseline after a 76% photobleach using a computerized dark adaptometer with targets centered at 5° on the superior vertical retinal meridian. Thresholds were measured over time until sensitivity recovered to a value of 5.0 X 10-3 scotopic cd/m2 . Time (minutes) to this event was defined as the rod-intercept (RI). The protocol was repeated at 6, 12, 18 and 24 months post baseline. For each eye a linear regression model was used to estimate the relationship between RI and time over 2 years. Slopes from these models were compared with respect to demographic and other variables.

Results : 30 eyes from 30 adults of European descent (mean age 74.2 yr, SD 6.6) were tested. There was no loss to follow-up. 7 of 30 eyes at baseline had RIs at or near ceiling (>25 min) that remained at ceiling over 2 years. For the remaining 23 eyes, mean slope was 0.18 (SD 0.23). The predicted RI increased on average by 4.3 min over two years (SD 5.6), ranging from a slight decrease of 1.4 minutes to an increase of 18.0 minutes. Variables at baseline associated with eyes having higher slopes (higher rate of RI increase over time) were age (p=0.020), smoking (p=0.017), and AMD family history (p=0.073).

Conclusions : Most intermediate AMD eyes exhibited RMDA slowing over 2 years, averaging a more than 4-minute RI increase. Some eyes at baseline had RIs at ceiling that remained there over 2 years. Characteristics known to be strong risk factors for AMD and its progression (age, smoking) were associated with greater RMDA delay over 2 years.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

×
×

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.

×