Abstract
Purpose :
To evaluate the prevalence of drusen at baseline and the conversion to neovascular age-related macular degeneration (AMD) based on fluorescein angiography (FA) and spectral-domain optical coherence tomography (SD-OCT) findings, in fellow eyes of the HARBOR study population. Previously, The Age-Related Eye Disease Study 2 (AREDS2) demonstrated that 35.5% (248 of 698 eyes) with bilateral large drusen and late AMD in one eye at baseline progressed to neovascular AMD over a median of 4.9 years of follow-up (The Age-Related Eye Disease Study 2 (AREDS2) Research Group, et al. JAMA Ophthalmol. 2014;132:142-9).
Methods :
This retrospective analysis of the 24-month, phase 3, randomized, double-masked, active-treatment controlled HARBOR study focused on the fellow eyes that had drusen (hard or soft) at baseline without the presence of neovascular AMD, defined as no neovascular AMD reported from history in the case report form, absence of choroidal neovascularization (CNV) on baseline FA, central subfield thickness (CST) <275 μm on baseline SD-OCT, and no subretinal fluid (SRF), cystoid space, intraretinal fluid (IRF), or pigment epithelial detachment (PED) on baseline SD-OCT. Fellow eye conversion was defined as presence of CNV on FA and any SD-OCT fluid defined as presence of SRF, cystoid space, IRF, PED, or CST ≥275 μm at any post-baseline visits.
Results :
In HARBOR, 352 fellow eyes had drusen without any neovascular AMD at baseline. Of these, 28 (8%) eyes had hard drusen and 324 (92%) eyes had soft drusen. At 24 months, eyes with soft drusen had a higher rate of conversion to CNV than eyes with hard drusen (18% vs 4%, respectively). While the proportion of eyes with hard drusen at baseline was small, 86% of them developed soft drusen by 24 months. Imaging case studies will be presented to illustrate these findings.
Conclusions :
In the HARBOR study, the majority of fellow eyes had soft drusen at baseline. Many of those with hard drusen at baseline converted to soft drusen over two years. Of fellow eyes with soft drusen and no neovascular AMD at baseline, 18% converted to CNV by 2 years. Such eyes should be carefully monitored for conversion to exudative AMD.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.