- Ocular Abnormalities: Babies will be excluded from this study if they have major congenital abnormalities in one or both eyes including microphthalmos, anophthalmos, anterior segment dysgenesis, dense corneal opacity, cataract, glaucoma, chorioretinitis, optic nerve hypoplasia, and chorioretinal coloboma. Eyelid abnormalities, such as severe blepharoptosis or severe hemangioma, that would likely affect vision, would also exclude a baby from participation. Minor abnormalities that would not be expected to affect vision may not be exclusion criteria including Mittendorf dot, mild blepharoptosis, limbal dermoid, and iris coloboma.