Progression of subretinal drusenoid deposits (SDD) in AMD revealed by adaptive optics laser scanning ophthalmoscopy (AOSLO)

Abstract

 

Purpose

 

To investigate the natural history of individual SDD, a lesion associated with progression of AMD, using high-resolution adaptive optics confocal imaging.

 

Methods

 

Four AMD patients with SDD were enrolled. 6 eyes were studied at baseline and 14 months later. Participants underwent color fundus photography, infrared, red-free, and autofluorescence scanning laser ophthalmoscopy, and spectral domain coherence tomography (SD-OCT). High-resolution retinal images were acquired with a new-generation research AOSLO. SDD were identified by multimodal imaging. A 3-stage SD-OCT-based grading system was used to classify SDD. The individual SDD identified at baseline and selected retinal areas were examined in AOSLO images to evaluate progression and new development of SDD.

 

Results

 

357 solitary SDD were identified at baseline. 51 (14.3%) were classified as stage 1, 60(16.8%) as stage 2, and 246 (68.9%) as stage 3. Over 14 months, of the 51 stage 1 SDD at baseline, 25(49.0 %) progressed to stage 2, 20 (39.2%) progressed to stage 3, and 6 (11.8%) remained at stage 1. Of the 60 stage 2 SDD at baseline, 52 (86.7 %) progressed to stage 3, 8 (13.3%) remained at stage 2. For the 246 stage 3 SDD at baseline, 20 (8.1%) disappeared. 226 (91.9%) remained at stage 3. 14 newly developed SDD were identified, 3 (21.4%) were of stage 1, 1 (7.1%) was of stage 2, and 10 (71.4%) were of stage 3.

 

Conclusions

 

AOSLO revealed unambiguous progression and regression of individual SDD. Mechanisms of lesion clearance remain to be determined. Intraretinal relocation of lesion contents is a possibility. With further measurement of individual SDD size and surrounding photoreceptor density over time, the progression rate of SDD and the impact of SDD progression on surrounding photoreceptors can be assessed. AOSLO, due to improved resolution, contrast, and fidelity, is particularly suitable for study of SDD dynamism, and thereby contributes to quantitative measures of disease severity, progression, and evaluation of treatment efficacy at the cellular level.

 

 

14-month follow-up in an 84-year-old woman (white non-Hispanic) with non-neovascular AMD (AREDS grade 7, BCVA 20/20). Over this time scale, SDD can appear (yellow, red arrows), expand (aqua, green, yellow), shrink (magenta arrows), and disappear (red and magenta arrowheads).

 

Keywords: 412 age-related macular degeneration • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 688 retina