Age- and sex-related changes in the soft tissues of the orbital region

The orbital region plays a predominant role in the evaluation of the craniofacial complex. In the current study information about normal sex-related dimensions of the orbital region, and growth, development and aging, were provided. The three-dimensional coordinates of several soft-tissue landmarks on the orbits and face were obtained by a non-invasive, computerized electromagnetic digitizer in 531 male and 357 female healthy subjects aged 4-73 years. From the landmarks, biocular and intercanthal widths, paired height and inclination of the orbit relative to both the true horizontal (head in natural head position) and Frankfurt plane, length and inclination of the eye fissure, the relevant ratios, soft-tissue orbital area, were calculated, and averaged for age and sex. Comparisons were performed by factorial analysis of variance. Biocular and intercanthal widths, length of the eye fissure, soft-tissue orbital area, and the inclination of the orbit relative to the true horizontal, were significantly larger in men than in women (p < 0.01), with a significant effect of age (p < 0.001), and significant age × sex interactions (p < 0.001). Orbital height, and the height-to-width ratio increased as a function of age (p < 0.001), but without gender-related differences. The inclination of the orbit relative to Frankfurt plane, and the inclination of the eye fissure did not differ between men and women, but modified as a function of age (p < 0.001), with different sex-related patterns (sex × age interaction, p < 0.001). On average, the paired measurements were symmetric, with similar values within each sex and age group. Overall, when compared to literature data, some differences were found due to both ethnicity, and different instruments. Nevertheless, during childhood, adolescence, and young adulthood, the age-related trends for linear dimensions were similar to those found in previous studies, while no previous data exist for older adults. During aging an increment in soft-tissue orbital area was found, with a progressive downward shift of landmark orbitale. Data collected in the present investigation could serve as a data base for the quantitative description of human orbital morphology during normal growth, development and aging. Forensic applications (evaluations of traumas, craniofacial alterations, teratogenic-induced conditions, facial reconstruction, aging of living and dead persons, personal identification) may also benefit from age- and sex-based data banks.