Abstract
Purpose :
The choroidal morphology and nature of pigment epithelial detachment (PED) associated with age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) has not been well characterized. The purpose of this study is to quantify the choroidal vascular structural changes underlying a PED using swept-source optical coherence tomography(SS-OCT)
Methods :
A prospective, cross-sectional study with multimodal imaging including dye angiography, SS-OCT and en face SS-OCT angiography was performed in eyes with PED associated with AMD and PCV. A PED was considered eccentric if it was located beyond 1500µm from the fovea.OCT images of the choroid were binarized into vascular lumen and stroma.Choroidal vascularity index (CVI) was quantified by determining the ratio of lumen area over the choroidal area in the subfoveal (SF) region and under the PED
Results :
Fifty age-matched control eyes and 105 eyes of 67 patients met the inclusion criteria.The mean age was 72.9± standard deviation (SD) 8.9years and 45(67.2%) were male.Sixty-six eyes (62.9%) had PCV and 39 eyes (37.1%) had neovascular AMD.The mean choroidal thickness (CT) and CVI under PED were significantly lower in AMD eyes vs control eyes(159.6 ± 64.5µm vs 221.2 ± 64.3µm, p<0.01 and 62.4 ± 5.3% vs 66.8 ± 11.4%, p<0.01). The CT and CVI under PED in PCV eyes were not significantly different from control eyes (234.5µm ± 89.7,p=0.36 and 65.0 ± 4.9%,p=0.32).In PCV eyes, the mean CT and CVI under PED were significantly higher than SF CT and CVI (246.3 ±95.8µm vs 220.5± 95.8µm, p=0.02)and ( 65.3±4.2%vs 62.2 ± 4.7%,p<0.01).There were 50 eyes (47.6%) with eccentric PED and the CT and CVI were significantly higher than SF CT and CVI(219.2 ±90.6µm vs 190.2 ±92.7µm, p<0.01) and (66.1 ±5.6% vs 62.1±5.3 %,p<0.01). Eighty-two eyes(78.1%) were vascularized PED which had significantly lower CVI than non-vascularized PED (64.4± 5.4% vs 66.8±5.9%, p=0.02) but there was no significant difference in CT(208.3 ±82.4µm vs 215.2± 92.8µm, p=0.58).
Conclusions :
Pathologically dilated choroidal vessels were found under the PED, which suggests choroidal hemodynamic disturbance in the pathogenesis of PED.Further longitudinal follow-up is required to study the prognostic implication of the changes in choroidal structure in response to treatment
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.