Longitudinal structure/function analysis in reticular pseudodrusen

Abstract

Purpose: To describe longitudinal structure/function correlations in eyes with progressive reticular pseudodrusen (RPD).

Methods: Thirteen eyes of 12 patients with exclusively RPD in the posterior pole were included (75.1 ± 5.7 years). All patients underwent spectral-domain optical coherence tomography (SD-OCT), confocal scanning laser ophthalmoscopy (cSLO), and multifocal electroretinography (mfERG) at baseline and 12-month follow-up. Size of retinal area affected by RPD, number and stages of RPD lesions, and choroidal thickness (CT) were quantified at baseline and at follow-up visit. Amplitudes obtained by mfERG in RPD eyes at baseline and follow-up were analyzed and correlated to morphologic changes. Eyes were compared to those of age-matched healthy controls.

Results: The total number of RPD lesions increased from 540 at baseline to 667 at 12-month follow-up. Mean CT was 198.5 ± 69.3 μm at baseline (control group 263.5 ± 42.6 μm; P = 0.005) and 189.2 ± 65.3 μm at follow-up (P < 0.001) (control group 265 ± 47.8 μm; P = 0.74). A mean growth of RPD-affected area of 3.3 mm(2) was measured. Multifocal ERG amplitudes decreased in both the study and control groups to a similar extent. Amplitudes differed significantly at the follow-up time point when compared between RPD-affected and nonaffected areas within the same eye. No correlations between changes of morphologic parameters and mfERG amplitude changes were found.

Conclusions: Multifocal ERG allows for detecting a decline of function over time in eyes with progressive RPD. Yet functional decline could not be correlated to changes in individual morphologic parameters.

Keywords: age-related macular degeneration; confocal scanning laser ophthalmoscopy; multifocal electroretinography; reticular drusen; reticular pseudodrusen; spectral-domain optical coherence tomography; subretinal drusenoid deposits.