Fundus Autofluorescence Imaging in Neovascular Age-Related Macular Degeneration: Potential Functional Implications

Abstract

Purpose: : To characterize the fundus autofluorescence imaging (FAF) of choroidal neovascularization (CNV) in patients with Age-related Macular Degeneration (AMD). FAF was described and correlated to CNV activity.

Methods: : One hundred consecutive cases of neovascular AMD evaluated at the Digital Angiography Reading Center (DARC) were enrolled. Patients underwent anti-VEGF therapy in the fellow eye. FAF and infra-red images were acquired by a confocal scanning laser ophthalmoscopy (Heidelberg Engineering, Germany). FAF pictures were also obtained with Topcon digital camera (Topcon, Japan), as well as other retinal imagings. The inclusion criterion was the presence of CNV in the macular area of the study eye. Exclusion criteria were previous photodynamic therapy (PDT) or laser photocoagulation in the study eye, or poor image quality. FAF patterns were described according to the presence, localization and inter-correlation of hyperautofluorescent, hypoautofluorescent, or normofluorescent areasç and then compared to color, red-free picture, and infra-red fundus pictures, and fluorescein angiography of the retina.

Results: : Neovascular AMD may present substantially different FAF patterns. Normal autofluorescence may occur in active CNV with preserved neurosensory retina. Prolonged or extensive active lesions tends to present hyperautofluorescence. Patterns of hypoautofluorescent areas are highly variable, and tend to correlate with photoreceptor and retinal pigment epithelium (RPE) loss. Lesion components such as fibrosis, subretinal blood and RPE changes may show high variability in FAF.

Conclusions: : Different than FAF patterns previously described for early AMD and geographic atrophy, FAF findings can be highly variable in neovascular AMD. However, because this imaging modality indirectly reflects photoreceptor and RPE metabolism and provides information on cell viability, FAF findings may indicate extent and severity of retinal cell loss and associated visual dysfunction. Our results indicate that qualitative analysis of FAF patterns in AMD neovascular lesions may correlate with CNV activity, but further analysis are needed to establish the clinical and prognostic implications of these findings.

Keywords: age-related macular degeneration • choroid: neovascularization • clinical (human) or epidemiologic studies: systems/equipment/techniques