Retinal blood flow velocity in patients with age-related macular degeneration

Abstract

Purpose/aim of the study: To study changes in retinal blood flow velocity in patients with early and neovascular age-related macular degeneration (AMD). We used the Retinal Function Imager (RFI, Optical Imaging Ltd., Rehovot, Israel), a noninvasive diagnostic approach for measuring blood flow velocity.

Materials and methods: Sixty eyes of 43 AMD patients and 53 eyes of 35 healthy individuals over the age of 50 were recruited for this study. All patients were scanned by the RFI with analysis of blood flow velocity of secondary and tertiary branches of arteries and veins. Differences among groups were assessed by mixed linear models.

Results: The average velocity in AMD patients was significantly lower compared to controls in arteries (3.6 ± 1.4 versus 4.3 ± 1.0 mm/sec, p = 0.009) but not in veins (2.6 ± 0.9 versus 3.1 ± 0.6 mm/sec, p = 0.08). When comparing the velocity between low- and high-grade AMD eyes, venous velocity was slower in the high grade AMD eyes only in the "narrow" group of vessels.

Conclusions: Decreased blood flow velocity in retinal arteries in patients with AMD was found. Despite the fact that AMD is essentially a choroidal disease, retinal vessels show a functional abnormality, which may suggest that the vascular abnormality in this disease is more generalized.