Functional Anatomic Correlates of Interface Lines Between Adjacent Facial Regions and Their Associated Vascular Networks.

Understanding the anatomic relationship between facial surface lines and underlying vascular networks is critical for safe dermal filler augmentation. This review presents a systematic taxonomy classifying facial surface changes into 5 categories-line, wrinkle, rhytid, crease, and fold-each with distinct vascular correlates that guide injection strategies. Creases and folds, forming at junctions between adjacent anatomic regions with differing tissue thickness, consistently overlie major arterial trunks that efficiently perfuse both sides. Key examples include the nasolabial, labiomental, preauricular, and corrugator creases, which serve as topographic markers for underlying vessels. Conversely, superficial wrinkles indicate more superficially coursing vessels, requiring deeper injection placement. Region-specific analysis reveals critical vascular landmarks: the supratrochlear and supraorbital arteries along the corrugator crease, the facial artery beneath the nasolabial fold, and the superficial temporal artery deep to the preauricular crease. Important venous structures, including the intercanthal vein at the nasal root and the angular vein traversing the nasojugal groove, pose additional risks due to cavernous sinus connections. This line-guided anatomic approach transforms visible surface features into a dynamic safety roadmap, enabling practitioners to preemptively identify high-risk vascular zones and select appropriate injection depths and techniques to minimize complications in facial aesthetic procedures.