Exophthalmometry in Mexican adults.

BACKGROUND: Up to the present time we do not know of any report about normal proptosis values in normal Mexican adults. Moreover, we think it is important to establish them in each population to distinguish between normal and pathological orbital processes because the values may vary in relation to ethnic factors.

SUBJECTS AND METHODS: Ocular protrussion values using Hertel's exophthalmometer were measured in 301 randomly selected normal adult subjects (185 females and 116 males), mean age 36 +/- 8.6 years, without known history of ocular trauma, surgery, endocrine disease or any ocular pathologic process.

RESULTS: The mean protrussion value was 15.18 +/- 2.16 mm for males and 14.82 +/- 1.98 mm for females. (p = NS). The distance between the lateral orbital rims was 97.78 +/- 3.97 mm for males and 94.33 +/- 1.98 mm for females (p < 0.001). We found a statistically significant difference between the values found in Mexican adults and those of American white and black subjects with enough data to make statistical calculations.

DISCUSSION: We established normal proptosis values for Mexican adults using Hertel's exophthalmometer. Ocular protrussion was lower than those reported in normal American black and white adults. We argue that the differences may be explained by different skull structure, and more specifically, orbital due to anthropological or racial differences.