Laser-induced defects of retinal development in chick embryos.

Retinae of 8-day-old chick embryos were exposed to laser beam irradiation and examined after hatching. The most prominent feature in the irradiated area was the presence of rosettes consisting of photoreceptors surrounded by an orderly arrangement of outer plexiform layer, inner nuclear layer and inner plexiform layer. The histological character of these rosettes raises questions of regeneration of retinal cells that have apparently withdrawn from the mitotic cycle and also the possibility of the regeneration of ganglion cell axons.