Abstract
Purpose :
Cholesterol crystals (CC) are highly reflective and common features seen by optical coherence tomography (OCT) and near-infrared reflectance (NIR) in eyes with non-neovascular age-related macular degeneration (NNV-AMD). To assess the origin of CC and their associated multimodal imaging (MMI) findings in eyes with drusenoid pigment epithelial detachment (DPED) secondary to NNV-AMD.
Methods :
This was a retrospective analysis of MMI, including serial eye-tracked OCT, NIR, color photography and fundus autofluorescence from 24 eyes with NNV-AMD that developed CCs in association with the spontaneous collapse of DPED. MMI features present prior to CC appearance were compared to those from a control group consisting of 14 eyes with NNV-AMD and DPED collapse not resulting in CC formation.
Results :
During DPED collapse, OCT showed CC forming at either the edge of nascent complete retinal pigment epithelium (RPE) and outer retinal atrophy (cRORA, 41.7%) or within the DPED between a split RPE+basal laminar deposit and Bruch’s membrane band (58.3%). The timing for CCs formation was 32.4 months (CI95% 23.2, 41.6) from the first visit. The CCs appeared as highly reflective single (50%) or multilaminar lines (25%). Some also appeared concomitant to refractile drusen (25%). Morphologic DPED features associated with CC formation were RPE disintegration (r=0.54, P=0.001), subretinal vitelliform material (r=0.53, P=0.002), outer retinal hyporeflective spaces (HS) (r=0.61, P<0.001), and a heterogenous DPED content (r=0.63, P<0.001). The frequencies of these DPED features were significantly higher in study vs. control eyes (RPE disintegration: 54.2% vs 14.3% (P=0.001), vitelliform material: 66.7% vs 28.6% (P=0.002), outer retinal HS: 20.8% vs 7.1% (P<0.001), heterogeneous content: 79.3% vs 14.3% (P<0.001).
Conclusions :
Specific MMI findings present in some eyes with NNV-AMD and DPED predict a greater risk of CC formation occurring during spontaneous DPED collapse. As eyes with CC have been shown to be at high risk for macular atrophy, the detection of these features may help identify certain AMD eyes at risk for future loss of central vision. The basis of the increased risk conferred by CC may be changes in the sub-RPE-BL environment associated with RPE degeneration, as recently shown for another feature visible on OCT, calcific nodules.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.