Choriocapillaris' alterations in the presence of reticular pseudodrusen compared to drusen: study based on OCTA findings.

Abstract

To evaluate the qualitative changes of choriocapillaris in the presence of reticular pseudodrusen (RPD) and compare them with conventional small drusen due to dry age-related macular degeneration (AMD). Participants in this study were 59 patients with non-neovascular AMD, presenting either RPD (23 patients) or drusen (36 patients) of similar size. All patients underwent best-corrected visual acuity, slit-lamp examination, spectral domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography. The morphology of RPD in SD-OCT was depicted either as conical or as amorphous in shape. Both types were found to affect the ellipsoid zone. The presence of RPD was associated with choriocapillaris' reduced blood flow signal (non-perfusion), while the same but less intense choriocapillaris' non-perfusion appearance was noticed in the presence of drusen of the same size. In 13% of patients with RPD, ghost-like vessels were observed in the non-perfusion area of choriocapillaris, while in none patients with drusen ghost vessels were present. In all 23 patients with RPD, the choriocapillaris non-perfusion was correspondent to the location of RPD. Additionally, in about 35% of them, choriocapillaris' impairment was also observed, covering areas outside RPD. Morphological impairment of choriocapillaris was more intense in patients with RPD than in those with conventional drusen of the same size. The existence of ghost vessels in the area of choriocapillaris' density defect suggested that choriocapillaris' alterations may occur in patients with RPD.