Figure 4. Retro-orbital injection of fluorescein isothiocyanate dextran (FITC)-dextran in newborn to P17 normal air mice. The superficial retinal vascular plexus grew outward from the optic nerve head (P0) to the peripheral tissue (P8), and the retinal vascular plexus of a P17 mouse was observed. Original magnification: 50×.