Abstract
Purpose :
UWF-FA allow visualization of up to 200 degrees of the retina in a single capture and are increasingly being used to evaluate non perfusion, vascular leakage and neovascularization. However, artifacts limit the view of the peripheral retina and interfere with image assessment. We aim to identify the image quality and impact of artifacts in evaluation of UWF-FA.
Methods :
UWF-FA images (Optos PLC Dunfermline, Scotland) from eyes with diabetic retinopathy (n=30) and retinal vein occlusion (n=30) were included. Images were from clinical trial submissions taken by certified photographers. Early phase images captured between 30 seconds and 1.5 minutes were evaluated. Image quality was evaluated in 14 regions using the Networc grid1 : fovea, macula, Zone 1,2 and 3 (each zone divided into superior, nasal, inferior and temporal). Quality assessment of each subfield was categorized as good, restricted view (< 50% of subfield) or ungradable (view restricted > 50% of the subfield). A zone was deemed ungradable when more than 1 subfield was determined ungradable. Regions with less than good quality were given reasons including: Lids/lashes, media opacity/floater, contrast/movement.
1https://malariajournal.biomedcentral.com/articles/10.1186/s12936-015-0897-7
Results :
All 60 eyes had at least one zone that was considered ungradable. The image quality was good with no artifacts in 67% of fovea, 68% macula, 45% zone 1 and 20% zone 2. There were no eyes with zone 3 categorized as good quality. Artifacts were present but the zone was still gradable in 23% fovea, 30% macula, 55% zone 1, 75% zone 2 and 38% zone 3. Ungradable rates were 10%, 2%, 0%, 5% and 62% respectively. The predominant reasons for ungradable images in fovea /macula region were floaters/media opacities (83%), media opacities in zone 2 (67%) and lash artifact in zone 3 (100%) .
Conclusions :
Ultra-wide field fluorescein imaging allows for an expanded view of the peripheral capillary network and reliable assessment up to the midperipheral retina in most eyes. Assessment of the far periphery may be limited due to artifacts.
This is a 2020 ARVO Annual Meeting abstract.