Facial Artery Asymmetry and Branching Patterns: Correlation With Main Trunk Diameter

Background: Most facial arteries (FAs) are characterized by left-right asymmetry, which is important to recognize to minimize vascular-related adverse events during minimally invasive anti-aging treatments. This study aimed to evaluate the feasibility of predicting vascular asymmetry before procedures by analyzing the correlation between the diameter of the main trunk (MT) of the FA and its left-right asymmetry. Methods: The distribution of 74 FAs in 37 Korean adult cadavers was analyzed. The diameter and running depth of each FA branch were examined. The left and right FA branching patterns were defined as balanced if they matched and asymmetric if not. Sides with more branches were classified as dominant, and those with fewer branches as recessive. Results: FA asymmetry was observed in 64.8% of cases, with the dominant type more frequent on the right (43.2%). In dominant types, the mean MT and winding part (WP) diameters were significantly larger ( P <0.05), with a close association to FA types. Dominant types were more frequent when the MT diameter was ≥3.0 mm, while recessive types predominated when ≤2.0 mm. The WP, nasolabial fold part, and angular artery ran through the subcutaneous layer in over 78% of cases, indicating a high risk of vascular injury. Conclusions: Measuring MT diameter using preprocedural ultrasound may help predict FA asymmetry and type, supporting patient-specific planning and reducing vascular complications in clinical settings.