BDNF and retinopathy of prematurity: Neurotrophins belong to a family of growth factors that promote neuronal as well as oligodendrocyte survival and differentiation both in the central and peripheral nervous systems.48,49 Although the focus has been on the ability of neurotrophins to protect and repair the neural system, they can also have a beneficial effect on the vascular system.22,50 We found that high concentrations of the neurotrophins NT-4 and BDNF were associated with a reduced risk for prethreshold ROP.