Abstract
Purpose:
Macular photoreceptor abnormalities with functional impairment have previously been associated with age-related macular degeneration (AMD) severity and particular AMD lesion types. We investigate whether ocular characteristics, the AMD status of the other eye, and person-based characteristics correlate with dark adaptation (DA) measured using the AdaptRxTM device (Apeliotus Technologies, Atlanta, GA).
Methods:
Participants aged >50 years ranging in AMD severity from no AMD to unilateral advanced AMD were enrolled. Participants underwent best-corrected visual acuity (BCVA) testing, ophthalmoscopic examination, multimodal imaging, and a low luminance questionnaire (LLQ). One eye was designated the study eye (excluding advanced AMD) for DA testing using the AdaptRxTM device, and rod intercept time (RIT) was measured. Study eyes were graded for AMD features (drusen, pigmentary changes, advanced AMD) to generate a person-based Simplified Severity Scale (SSS) score, with scores from 0 through 4. Subfoveal choroidal thickness (SFCT) was measured with enhanced depth imaging OCT. Presence of reticular drusen (RD) was assessed by masked grading of fundus images and confirmed with OCT. Nonparametric statistical testing was performed on all comparisons.
Results:
A total of 119 study eyes in 119 participants (mean age=74.5±9.6 years, 58.8% female) were enrolled. Across all study eyes, increased RIT was significantly correlated with increasing age (r =0.33, p=0.0003), decreasing BCVA (r =-0.52, p<0.0001), pseudophakia (p=0.03), decreasing SFCT (r =-0.27, p=0.003), and decreasing LLQ scores (p<0.004 for all comparisons). When categorized by participant SSS score, DA testing revealed increasing mean RIT with increasing score, with scores of 2, 3, or 4 demonstrating significantly increased RITs compared to a score of 0 (p<0.001 for all comparisons). Study eyes with RD (16/119, 13.4%) had a significantly greater mean RIT compared to eyes without RD in any AMD severity group (p<0.02 for all comparisons).
Conclusions:
Impairments in DA appear to increase with AMD severity as defined by increasing large drusen and pigmentary changes (SSS). Additionally, the presence of RD was strongly associated with severe DA impairment regardless of SSS score.
Keywords: 412 age-related macular degeneration •
465 clinical (human) or epidemiologic studies: systems/equipment/techniques •
414 aging: visual performance