OPTIC-NERVE HYPOPLASIA - COMPARATIVE EFFECTS IN CHILDREN AND RATS EXPOSED TO ALCOHOL DURING PREGNANCY

Children with the fetal alcohol syndrome often have ocular anomalies. These include abnormalities of the eyes and adnexa (strabismus, blepha roptosis, epicanthus), as well as intraocular defects (cataract, glauc oma, persistent hyperplastic primary vitreous, retinal and optic nerve anomalies). Based on the clinical results in an ophthalmological stud y of a group of Swedish children with the fetal alcohol syndrome, in w hich optic nerve hypoplasia was found in up to one-half of the group, an experimental study was designed in rats pre- and perinatally expose d to alcohol by means of a liquid diet. The optic nerve was seriously affected. Macroglial cells and optic axons were ultrastructurally dama ged. The diameter of the optic nerve cross section, glial cell nuclear area, axonal diameter, and the total number of optic axons showed sig nificantly lower values in the alcohol-exposed group than in the contr ols. In addition, the retina from the alcohol-exposed animals displaye d significantly lower values of the retinal thickness and ganglion cel l nuclear volume, as compared to the controls. Thus, rats exposed to a lcohol in utero developed hypoplasia of the optic nerve similar to the findings in children born to alcoholic mothers. This strongly support s the hypothesis that prenatal alcohol exposure may adversely affect t he development of the optic nerve. (C) 1994 Wiley-Liss, Inc.