Adaptive optics scanning laser ophthalmoscopy characterization of cone photoreceptor reflectivity perturbation by drusen and subretinal drusenoid deposits

Abstract

AbstractPurpose: To examine the structure of photoreceptors around drusen and subretinal drusenoid deposits (SDD) in patients with age‐related macular degeneration (AMD) using multimodal imaging, including adaptive optics scanning laser ophthalmoscopy (AOSLO).Methods: Thirty‐four (n = 34) patients with early to intermediate AMD were enrolled and classified into 3 groups based on predominant lesion type. Group 1 included 20 eyes of 15 subjects with medium‐large soft drusen (63–1000 μm diameter), group 2 had 15 eyes of 10 subjects with cuticular drusen (<63 μm), and group 3 had 14 eyes of 9 subjects with SDD. Lesion presence was ascertained by colour fundus photography, near‐infrared reflectance, blue reflectance, autofluorescence, and spectral‐domain optical coherence tomography (SD‐OCT). SDD were classified with a 3‐stage OCT‐based grading system. In addition, the reflectivity and packing mosaic of cone photoreceptors were assessed with AOSLO.Results: AOSLO revealed characteristic photoreceptor reflectivity perturbation by different types of AMD's extracellular lesions. Around large soft drusen, the photoreceptor mosaic was invisible at the edge and visible on the top. The photoreceptors in the retinae with cuticular drusen were largely maintained as a contiguous mosaic but with reduced reflectivity over the lesions. Photoreceptors surrounding SDD showed reduced reflectivity associated with the SDD stage. The en face appearance of the photoreceptor mosaic was consistent with its cross‐sectional structure as rendered by SD‐OCT.Conclusions: The dramatic photoreceptor reflectivity perturbation associated with SDD indicates that SDD may impose a more direct and severe impact on overlying photoreceptors than drusen, suggesting that the retinal function in eyes with SDD may be more severely impaired.@@@@