The nose is made up of a fixed and rigid part that is called nasal pyramid, although it rather has the shape of a tent or roof, and a pliable mobile part which is the nasal tip, the alae and its annexes. The nasal tip and the alae are structured by the so called alar or lower lateral horseshoe shaped cartilages with their lateral and medial crura or crus and accessory cartilages, the domes between lateral and medial cruras, the interdomal fibrofatty pad, the caudal or lower septum and the skin of the alae.
Both halves of the nasal tip join with each other in the center of the tip to form a tripod in which the lateral legs are the lateral cruras of the alar or lower lateral cartilages and the central leg the union of both medial cruras of the alar or lower lateral cartilages.
The columella or central portion between the nostrils can be too visible (normally only from 2 to 4 mm of septum mucosa should be seen) due to different causes which might coexist in one particular case; one very common cause of columellar show is the alar retraction (the side curtain covering the columella sets too high), however this is not a really hanging or protruding columella, just the alar rims are unable to cover it; thick alar or lower lateral cartilages medial cruras may cause a real protrusion (not a hanging one) of the columella since these cruras lie just beneath the columellar skin; a long septum pushes down the columella making it too visible (neither hanging) as well; finally some aging tip cases may also suffer from really hanging columella due to the aged and stretched ligaments supporting the columella failing to play their structural role.
When the columella is too visible for whatever reasons the infratip lobule is oversized and prominent, the septal mucosa is also exposed or visible and the nostrils are larger than usual, with frequent association with bulbous tip and parenthesis tip deformity, being the overall nasal look grotesque and artificial, leading to lack of suitable femininity in women and an unsightly look in men.
Treatment of columellar show has to be customized to each individual situation; for retracted alar rims the main pillar are techniques of alar or lower lateral cartilages grafting and repositioning, combining either alar cartilages batten, strut or replacement grafting; for thick medial cruras and aging cases the treatment is based on trimming such cartilaginous medial cruras and eventually apply the tongue in groove maneuver, plasties, plications (shaping sutures through the cartilages), nasal tip grafting, with or without reinforcement of tip support with columellar strut.