Localization and Staging of Vascular Adverse Events After Facial Fillers: A Detailed Assessment.

[BACKGROUND] Vascular adverse events (VAEs) are among the most feared complications following filler injections. At the specialized filler-complication clinic, the authors observed that the lateral region of the face experiences a lower risk of VAE-associated necrosis compared with the medial region.

[OBJECTIVES] The authors of this study aim to determine whether the medial facial region has a higher risk of necrosis following dermal filler injections compared with the lateral facial region. To assess this observation statistically, the authors analyzed all VAE cases reported between 2019 and 2024.

[METHODS] A retrospective analysis was undertaken. High-resolution photographs enabled precise anatomical localization and accurate staging of the VAEs. The face was anatomically subdivided utilizing 3 separate classification methods: (1) facial zones based on the 4 primary arteries (ophthalmic, superficial temporal, maxillary, and facial arteries); (2) classification based on whether subzones were supplied by branches of the external carotid artery or by both the external and internal carotid arteries; and (3) categorization into the medial or lateral region of the face, based on their relative location to the line of ligaments. The clinical patterns of VAEs were classified into 5 stages, distinguishing between non-necrotic (Stages 1 and 2) and necrotic (Stages 3-5) outcomes, reflecting a stepwise clinical development of symptoms over time. Statistical analyses, including and Fisher's exact tests, were utilized to evaluate the distribution of VAE stages within each of the 3 anatomical classification methods.

[RESULTS] In total, 120 patients with documented VAEs between 2019 and 2024 were included. Necrotic VAEs (Stages 3-5) occurred significantly more frequently in the medial facial region ( = .048). No significant correlation was found between these stages and distributions of both carotid artery branches nor the primary facial arteries.

[CONCLUSIONS] In this study, the authors highlight a higher risk of necrosis following dermal filler treatments in the medial facial region compared with the lateral region. A correlation between necrosis and the distribution of facial primary arteries or the carotid arteries seems to be absent, suggesting that local factors (eg, number or function of anastomoses/choke anastomoses) may play an important role.