Anthropometry of Soft-Tissue Orbits in Bulgarian Newborns: Norms for Intercanthal and Biocular Widths and Length of Palpebral Fissures in 100 Boys and 100 Girls

Abstract

OBJECTIVE: To establish early postnatal norms for the main measurements of the soft-tissue orbits for the Slavic Bulgarian population (9 million), we measured intercanthal (en-en) and biocular width (ex-ex) and length of the palpebral fissures (ex-en) in a representative sample of newborns less than six days old. METHOD: Eye measurements were taken with a sliding caliper from randomly chosen subjects by the senior author using standard anthropometric methods. Findings were compared to those published for other Caucasian ethnic groups of infants (Germans and two groups of North American Caucasians). RESULTS: The mean values of all three soft orbital measurements were greater in newborn Bulgarian boys than girls. Measurements of Bulgarian intercanthal width (en-en) were greater in both sexes but those of biocular width (ex-ex) and palpebral fissure length (ex-en) were less than those that have been reported for North American Caucasian infants. Bulgarian intercanthal and biocular measurements were wider than German babies in both sexes. Differences, although small, were statistically highly significant but greatly influenced by differing sample sizes and subject age among the four Caucasian populations. CONCLUSION: Anthropometric differences between ethnic groups of Caucasians already exist shortly after birth. Knowledge of the soft orbital data in early stages of the postnatal development in healthy populations is essential for determination in individuals of deviations from normal data. These Bulgarian norms can be helpful in anthropometric studies of the ethnically mixed Caucasian populations of North America.