Retinal Sensitivity in non-exudative Age-Related Macular Degeneration: Longitidunal analyses using validated automated algorithms

Abstract

Purpose : The aim of this study was to evaluate the retinal sensitivity of eyes with drusen during the course of non-exsudative age-related macular degeneration (AMD).

Methods : In a regular follow-up scheme of every three months for one year, retinal sensitivity of 30 eyes of 30 patients with early or intermediate AMD was assessed by mesopic testing using a grid of 45 stimulus points (Nidek MP3, Italy). Eyes were consecutively scanned using Spectralis SD-OCT (scanning area 20°x20°, volume scan 1024x97). Volume and area of drusen in each eye as well as the presence of pathognomonic AMD features were determined using in our department developed and validated automated algorithms. Subretinal drusenoid deposits, hyperreflective foci, discontinuities of the RPE and/or IS-OS layer and inhomogeneous drusen content served as pathognomonic AMD features.

Results : The mean age of the patients was 76.85 years (±6.6). Automated segmentation successfully located and quantified AMD-related alterations. The mean sensitivity was 25.6 dB at baseline and 28.3 dB at 12 months, the mean drusen volume was 0.035mm² and 0.042mm² respectively (p>0.05). Within one year, retinal sensitivity did not show a significant deterioration during time on individual eyes. No correlation between the total drusen volume and the mean sensitivity was found. The best correlation between drusen volume and retinal sensitivity were found within the 3 mm area. Furthermore, retinal sensitivity was shown to be significantly worse, the more morphological features of later stages of non-exsudative AMD were present (p<0.01).

Conclusions : Automated segmentation successfully located and quantified AMD-related alterations. Automated algorithms may be used as ideal tools for monitoring morphological progression consistent with functional loss. Progression of disease from early to intermediate stages of non-exsudativ AMD, characterized by progressive accumulation of morphologic markers, was associated with significant reduction of retinal sensitivity.

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