Abstract
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 χ (2) 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 (P = .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.