Purpose: The purpose of this study was to quantitatively investigate the haemodynamics and oxygen transmission of the retina.
Methods: Considering the effect of Fåhraeus-Lindqvist effect on the apparent viscosity of blood and the actual haematocrit in blood vessels, this study used the currently known retinal parameters (e.g. blood flow obtained by Doppler Fourier domain optical coherence tomography, FD-OCT for short) to construct a retinal blood circulation model consisting of an asymmetric vascular network system.
Results: The blood flow velocity and the vascular diameter in the retinal blood vessels satisfied the exponential relationship. The wall shear stress was related to the release of nitric oxide synthase and endothelin-1 by endothelial cells and played an important role in retinal blood flow regulation. In the retinal arteries, the oxygen tension ranged from 98 to 65 mmHg, and the oxygen saturation ranged from 97.3% to 92.2%. In the retinal veins, the oxygen tension was approximately 41.8 mmHg, and the oxygen saturation ranged from 79.2% to 77.3%. The difference in oxygen content of the arteriovenous network was 5.4 (ml O2/dl blood), and the oxygen extraction of the superior temporal arteriovenous network was 86 (μl/min*ml O2/dl blood).
Conclusion: Compared with previous relevant experimental data, the numerical model established in this article demonstrates reliability. It also helps advance our understanding of the retinal pathological processes related to hemodynamics and metabolism.
Keywords: Asymmetric retinal networks; Fåhraeus-Lindqvist effect; haemodynamics; mathematical method; oxygen transmission.