Objective: We examined the potential teratogenic effect of endoscopic white light on the developing visual pathways.
Study design: The right eye of chicken embryos (n = 22) was exposed to maximal endoscopic light intensity on day 10 of development. At day 17 of development the histologic characteristics of the light-exposed retinas were compared with those of the control embryos (n = 4). Normal functioning of the light-exposed eye was assessed by intravitreal injection of wheat germ agglutinin-horseradish peroxidase and observation of its axonal transport pattern to the diencephalic and mesencephalic visual centers. Axonal transport patterns were compared with those found in previous studies of normal embryos. Behavioral feeding patterns were compared between two groups of newly hatched chickens, one exposed to endoscopic light after hatching (n = 13) and the other, an unexposed control group (n = 12).
Results: No evidence of retinal damage, altered axonal transport or altered feeding patterns could be found between control and experimental animals.
Conclusion: Endoscopic white light does not appear to be harmful to the developing retina and visual pathway.