Developemnt of the human optic disc: light microscopy.

Human embryonic and fetal optic discs were studied in semi thin sections stained with silver and toned with gold, in a series ranging from 7 to 21 weeks of gestation. The observations suggest that Bergmeister's papilla forms by proliferation of glial cells in the optic disc rather than by sequestration of retinal glia by axons growing through the region. A possible stimulus for such a glial proliferation is hypothesized to be traction on the anterior face of the disc exerted through the primary vitreous. The formation of the glial sheath of the hyaloid artery also appears to be a consequence of traction from the primary vitreous.