Nasal measurements that are 2 standard deviations or more below the mean. Assessment of nasal height, width and protrusion is usually made. Nasal height is the vertical distance between the base of the columella and the nasion. Nasal width is the horizontal measurement between the outer margins of the alae nasi. Nasal protrusion is the measurement from the nasal tip to the base of the columella – best appreciated in profile. In clinical practice, identification is most often made subjectively, and reduction in protrusion or underdevelopment of the nasal bridge are the commonest presentations.
Protrusion of the nasal tip and integrity of the bridge are best appreciated in the midsagittal plane. The nose may also be viewed in coronal and transverse planes.
Prominence of the eyes may suggest relative lack of protrusion of the nose. Increased length of the philtrum may lead the observer to believe nasal height is reduced.
Nose appears flattened (reduced protrusion)
Nasal bridge may appear low-placed/scooped in profile
All nasal dimensions may be reduced
- Phenytoin embryopathy
- Thanatophoric dysplasia
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