Normal exophthalmometric values in children.

We used a Hertel exophthalmometer to measure the degree of ocular protrusion in 852 subjects who had no history of orbital trauma or disease, endocrine disease, severe myopia, buphthalmos, or craniofacial deformities. The subjects ranged in age from 3 to 10 years. No statistically significant difference was observed between boys and girls or between right and left eyes in each age group. The mean normal protrusion values ranged from 9.11 mm in the 3-year-old group to 11.67 mm in the 10-year-old group. The mean outer orbital margin distance ranged from 78.7 mm in the 3-year-old group to 89.1 mm in the 10-year-old group. The data obtained were tabulated to plot percentile distribution curves of normal exophthalmometric values and outer orbital margin distance in children. No subject had more than 2 mm of asymmetry between the eyes.