As the retina is a developmental outgrowth of the diencephalon (Purves, 2001; Erskine and Herrera, 2014), it shares many vascular morphological and physiological features with cerebral vessels (Patton et al., 2005; Crair and Mason, 2016). For instance, the retina has a highly selective blood retinal barrier (BRB), with many similar structural and functional properties as the BBB, which modulates the influx of ions, proteins and water, as well as limits the infiltration of circulating immune cells (Cunha-Vaz et al., 2011). The recent identification of an ocular glymphatic drainage system in rodents, clearing fluids and metabolites such as Aβ from the retina and vitreous via an aquaporin-4 (AQP4)-dependent pathway, is a sign of yet another structural and physiological similarity shared by the brain and retina (Wang et al., 2020). The same group also demonstrated that this clearance route may be impaired in ocular conditions associated with retinal damage such as glaucoma (Wang et al., 2020). Whether similar glymphatic drainage occurs in the human eye and the extent to which disruptions in this process contribute to pathological changes in neurological diseases such as AD remain to be investigated.