Despite recent advances in vascular biology, the mechanisms underpinning vascular development remain poorly understood. It is therefore crucial to gain further insight into the mechanisms governing the formation of complex vascular networks and their response to external stimuli. The translation of these results holds the key to the improvement of therapies modulating vascular patterning and sprouting for the treatment of retinopathies or cancer. One of the pressing questions in the field is establishing how primitive vessel networks remodel into a hierarchically branched and functionally perfused network of arteries, arterioles, capillaries, and veins. In recent years, the main molecular mechanisms regulating endothelial cell behaviour during vessel formation have been elucidated using experimental techniques. However, important challenges remain: i) understanding how molecular- and cell-level mechanisms integrate to give rise to systems-level behaviour and; ii) understanding the impact on vascular patterning of the interplay between molecular regulation and haemodynamic forces (i.e. vascular mechanotransduction). In this talk, I will present recent advances on the development of high-resolution computational blood flow models from confocal microscope images of mouse retina (a common animal model for the study of developmental vascular remodelling). Our results show that the flow patterns in the system are complex and that vessel segments undergoing regression are preferentially located in regions of low wall shear stress.