Table 6 Anatomical Soft Tissue Landmarks, Reference Planes, and Measurement Parameters Adopted for 3D Nasal Morphometric Analysis.
From: Patient- and 3D morphometry-based nose outcomes after skeletofacial reconstruction
Parameters (abbreviations) | Definitions |
|---|---|
Landmarks | |
Nasion (N) | Most depressed midline point superior to the nasal bridge |
Pronasale (Prn) | Most anterior midpoint of the nasal tip |
Subnasale (Sn) | Midpoint on the nasolabial contour between the columella crest and the upper lip |
Columellar constructed point (C) | Breakpoint at the end of the tangential line drawn from the Sn along the lower part of columella |
Alare (Al) | Most lateral point on each alar contour |
Exocanthion (Ex) | Point located at the outer commissure of each eye fissure |
Labial superius (Ls) | Midpoint of the vermilion line of the upper lip |
Tragion (T) | Point located at the upper margin of each tragus |
Reference planes | |
T-Ex plane | Line passing through the T and Ex points |
Frankfurt-horizontal (Fh) plane | Line passing through the T point and 17.6 degrees below the Ex-T plane |
Linear measurements | |
Nasal length | Linear distance between N and Prn points |
Nasal height | Linear distance between N and Sn points |
Nasal protrusion | Linear distance between Sn and Prn points |
Alar width | Linear distance between right Al and left Al points |
Nasal tip projection | Linear distance from coronal plane intersecting the alar facial groove and perpendicular to the Fh plane to Prn point |
Angular measurements | |
Nasal dorsum angle | Angulation calculated from intersecting lines drawn from the N to Sn points and from N to Prn points (Sn – N – Prn) |
Columellar angle | Angulation calculated from intersecting lines drawn from the N to Sn points and from Sn to C points (N – Sn – C) |
Columellar–labial angle | Angulation calculated from intersecting lines drawn from Sn to C points and from Sn to Ls points (C – Sn – Ls) |
