External nasal parameters in Egyptians: an in-depth nasal photogrammatic analysis

Abstract

As ethnic influences can result in different appearances of the nose, the purpose of this study was to provide a set of standard values of the external form of the nose with special emphasis on the influence of age and sex on these values to establish norms for the Egyptians. Several soft-tissue landmarks on the external nose were obtained by a non-invasive, photogrammetric analysis in 1,000 healthy Egyptians aged 20-70years. From these landmarks, ten linear distances and six nasal angles were measured and six nasal indices were calculated. A significant sexual dimorphism was found for nasal external volume and area and most linear distances where males presented with higher values than those in females of the corresponding age except for alar length where females showed higher values. Moreover, age significantly influenced nasal volume, area and distances as they showed statistically significant increase till old age. Concerning angles, nasofrontal, nasofacial, nasomental and nasolabial angles were wider in females while mentocervical angle was wider in males. Moreover, nasofrontal, mentocervical and alar slope angles showed significant increase with advancing age while nasofacial, nasomental and nasolabial showed significant decrease. Regarding nasal indices, sexual dimorphism was recognized for anatomic nasal index, nasal tip protrusion, nasal height ratio and nasal tip protrusion-nasal width indices. Moreover, results also showed that the Egyptians have a Mesorrhine type of nose. Data collected in the present investigation could serve as a database for the quantitative description of the Egyptian nasal morphology.