Surgical anatomy of the nose is complex and requires a three dimensional understanding acquired only by a surgeon familiar with rhinoplasty. What follows is a simplified overview of the main structures and their common names so one can better follow further descriptions of surgical options and alternatives.
The external covering of the nose is composed of the skin, subcutaneous tissue, a thin layer of supporting tissue (SMAS), and blood vessels.
B = Base (also, root or nasion)
D = Dorsum (also, spine): extends from B to L
L = Lobule: bottom of nose flanked by alae
T = Tip: highest point on the lobule
A = Alae: wide wings rimming the nostrils
C = Columella: central area between nostrils
Below the Skin
(Note: The skin here is shown still attached to the lower third of the nose.)
Beneath the skin sits a thin layer of muscle and fascia that animates the nose.
The columella normally sits 1-2 mm below the nostrils.
Below the Muscle
The lower two-thirds of the nose consists of a variety of highly shaped cartilages (green). At the point where the cartilage meets the bone, there is often a slight change of direction or a bump. This is also the area where the nose is usually the widest.
There is also often a slight break where the cartilage of the dorsum meets the cartilage of the tip. From there, the tip usually shows a slight change in direction as it curves slightly more forward.
The alar "wings" are mostly fat (yellow) rather than cartilage, giving this part of nose a softer contour.
Only the top third of the nose contains bone (a paired set of nasal bones attached to the skull's maxillary and frontal bones), which projects the nose forward from rest of the facial skeleton.
The bottom two-thirds of the nose is supported by cartilage (shown in the previous illustration).