Answer:
The primary blood supply to the nasal tip derives from the lateral
nasal branches from the angular artery. The lateral nasal artery is present
in 97% of cadaver dissection and is located 2-3 mm superior to the alar
groove within the subdermal plexus. The columellar artery is a branch of
the superior labial artery but is present only 77% of the time and is bilateral
only 9% of the time. The columellar artery also is located in the subdermal
plexus but is generally smaller in caliber and less consistent in its presence.
The anterior ethmoid and dorsal nasal branches of the ophthalmic artery
also anastomose with tributaries. The findings explain the safety of transcolumellar
incisions in open rhinoplasty but tip refinement is best achieved through
contouring the nasal framework while avoiding defatting to the dermal level
because of the risk of compromising blood supply.