Choroidal maps in non-exudative age-related macular degeneration

Purpose To compare choroidal thickness maps (CMs) in patients with non-exudative age-related macular degeneration (AMD) and control subjects using swept source optical coherence tomography (Swept-OCT). Methods CMs were automatically measured in the different Early Treatment of Diabetic Retinopathy Study (ETDRS) sectors in eyes with early non-exudative AMD (early AMD) (large soft drusen: group 1; reticular pseudodrusen: group 2 and variable combination of large soft drusen and reticular pseudodrusen: group 3), late non-exudative AMD/geographic atrophy (GA) (late AMD) (group 4) and control subjects (group 5). Fundus autofluorescence (FAF) images were overlaid to sectorial CMs in late-AMD group (group 4). Results A total of 90 eyes (90 patients, 79.7 +/- 8.34 years old) were included. CMs were significantly reduced in early-AMD group 2 and 3 and late-AMD group 4 compared with control subjects in group 5 and early-AMD group 1 (large soft drusen alone) for each ETDRS sectors (p<0.05). No difference in CMs was found by comparing group 2 with 3 and group 2 and 3 with group 4. No statistical differences in CMs were found among ETDRS sectors with >50% absence of FAF ('Hypo FAF' sectors) resulting from retinal atrophy versus <= 50% absence of FAF ('hyper/iso FAF' sectors owing to >50% preserved retina) in late-AMD group (group 4) (p=0.328). Conclusions CMs appeared thinner in early nonexudative AMD with intermediate distribution of reticular pseudodrusen versus control subjects and early non-exudative AMD with drusen alone. Same results were found in the group with variable combination of large soft drusen and reticular pseudodrusen. In GA eyes, a choroidal thinning could be detected independently of the retinal pigmented epithelium status.