Abstract
Purpose :
To evaluate appearance and lesion size of inflammatory lesions on fundus autofluorescence (FAF) imaging modalities using four different excitation wavelengths.
Methods :
Eyes were imaged with confocal laser scanning ophthalmoscopy (EIDON, CenterVue), 450 nm excitation with color-coded emission detection FAF (EIDON, CenterVue, Italy), 488 nm, 518 nm and 820 nm excitation grey-scale FAF (Spectralis HRA, Heidelberg Engineering, Germany). Appearance of inflammatory lesions (hypo-, iso- and hyperautofluorescence) was compared between the different FAF modalities and with color fundus photography (CFP) and funduscopy. Patients with media opacities impairing image quality were excluded.
Results :
Sixty-six eyes (41 patients, 25 with bilateral disease) with posterior or panuveitis were included. Mean age was 51.7 ± 17.7 years and 38 (58%) were male. Appearance on FAF varied between FAF modalities in terms of hyper-, iso- or hypoautofluorescence. For example funduscopically visible lesions were also visible on 450 nm FAF, however not visible on other FAF modalities (16 eyes, 24%). Funduscopically bright lesions appeared hypoautofluorescent on 488 nm, 518 nm and 820 nm FAF but were hyperautofluorescent on 450 nm FAF (3 eyes, 4.5%). Hyperautofluorescent appearance of different lesions in the same eye both increased or decreased with increasing excitation wavelength (9 eyes, 14%). In some cases lesion size was larger on FAF compared to CFP (3 eyes, 4.5%). Some funduscopically not or just merely visible lesions were well visible on FAF and appeared hyper- or hypoautofluorescent (29 eyes, 44%).
Conclusions :
Appearance of the same inflammatory lesions can vary considerably between different FAF modalities dependent on excitation wavelength. This might be due lesions affecting different retinal and/or choroidal layers in combination with different penetration depth of FAF wavelengths and/or excitation of a different range of fluorophores. Future studies need to assess the clinical implications of these findings.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.