Why Does an "Avatar Nose" Appear After Dermal Filler Injection? Insights From a Cadaveric Study on the Nasofrontal Ligament.

Background: Nonsurgical rhinoplasty (NSR) with dermal fillers has gained popularity because of its immediate and visible results, minimal downtime, and long-lasting effects. However, complications such as filler migration can lead to the development of the "Avatar nose," a condition where the nose appears unnaturally wide and bulbous in the nasion area, disrupting facial harmony. This phenomenon is often exacerbated by the presence of a taut nasofrontal ligament, which tethers the periosteum to the dermal layer and influences nasal contour.

Objective: This study aims to introduce and define the nasofrontal ligament, a previously unrecognized anatomical structure identified during cadaveric dissection, and to measure the penetration force required to traverse this ligament in the context of NSR. By exploring these aspects, the study seeks to enhance the understanding of nasal anatomy and improve the precision and outcomes of filler-based NSR.

Methods: The study involved the dissection of 2 fresh-frozen human cadaveric specimens, during which the nasofrontal ligament was identified. Penetration force was measured using a motorized force tester, with a standardized cannula depth of 5 mm. The force required to traverse the nasofrontal ligament was compared with a control point devoid of ligaments and muscles.

Results: The nasofrontal ligament required a significantly higher penetration force compared with the control point, highlighting its structural integrity and potential impact on filler migration. These findings suggest that subcision of the ligament could prevent the development of the "Avatar nose" and improve the outcomes of NSR.

Conclusion: This study introduces the nasofrontal ligament as a key anatomical structure in NSR and demonstrates its influence on filler migration. Subcision of this ligament may enhance filler stability and aesthetic outcomes. However, the study's limitations, including a small sample size and the exclusive use of Korean cadavers, suggest the need for further research across diverse populations to validate these findings and refine NSR techniques.