The Vermilion Canal: A Longitudinal Potential Space Beneath the Vermilion Margin Explaining One Point, Linear Filler...

Area of Science:

• Anatomy
• Dermatology
• Plastic Surgery

Background:

• Clinicians observe filler material tracking along the lip margin after injection.
• This phenomenon suggests an underlying anatomical pathway at the mucocutaneous junction.

Purpose of the Study:

• To identify a consistent anatomical structure, termed the "vermilion canal," deep to the vermilion border.
• To characterize tracer spread patterns from single injection points along the vermilion border.

Main Methods:

• Injection of dyed gel filler into the vermilion border of ten adult cadavers (one puncture site per lip).
• Macroscopic examination of tracer distribution, followed by layered dissections and cross-sections to define anatomical planes.

Main Results:

• A longitudinal, canal-like potential space was identified deep to the vermilion border in 90% of specimens.
• Tracer predominantly spread within this space, forming a continuous column with limited central lip dispersion.
• The vermilion canal was consistently observed in both upper and lower lips, related to the orbicularis oris muscle.

Conclusions:

• A reproducible "vermilion canal" exists beneath the lip border, explaining linear filler tracking.
• This anatomical finding supports a targeted injection approach for achieving a crisp vermilion border.
• Understanding the vermilion canal aids in optimizing cosmetic filler procedures and managing potential vascular risks.