Abstract
Purpose :
We have previously reported in flat mounts the 3 major autofluorescence (AF) emission spectra of the retinal pigment epithelium (RPE) and the combined spectra of drusen/sub-RPE deposits in age-related macular degeneration (AMD) (Tong et al, RETINA, 2016 and Ann Eye Sc, 2021). Basal laminar sub-RPE deposits (BLamD) specifically appear to be the source of increased autofluorescence (AF) of lesions of geographic atrophy (GA) associated with subretinal drusenoid deposits (SDDs) versus drusen-associated GA lesions (Wei et al, Eye, 2023). Here in retinal cross sections, we acquire and characterize specifically the AF spectrum of BLamD to assist research on its molecular composition and pathophysiologic origin.
Methods :
Hyperspectral AF images were acquired from 13 retinal cross sections and 82 anatomically identified BLamD regions of interest (ROIs) in the macula of 4 AMD donors with intermediate AMD at emissions from 420 to 720 nm in 10 nm steps at four excitation wavelengths (λex 436, 450, 480 and 505 nm) as previously described (See Figure). The emission spectra of the ROIs were recorded, together with the wavelength locations (nm) of their peak amplitudes.
Results :
The mean peak locations in retina cross sections of the emission spectral peaks from 82 BLamD ROIs (excitation wavelengths 436, 450, 480, and 505 nm) were 527.6 ± 7.5, 529.4 ± 8.1, 557.4 ± 9.2, and 565.6 ± 5.5 nm, respectively, all longer wavelength than those reported for combined drusen/sub-RPE deposits in flat mounts (~510, 520, 530, 540 nm).
Conclusions :
The mean hyperspectral AF emission peak locations for BLamD specifically in AMD donors at 4 excitation wavelengths were all longer wavelength than those previously reported for combined drusen/sub-RPE deposits, suggesting a different fluorophore composition for BLamD. These hyperspectral AF data can assist research on the molecular composition of BLamD and the pathophysiology of its association with SDDs in AMD.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.