BACKGROUND: Skin ischemia is a severe complication of nasolabial fold (NLF) hyaluronic acid filler injections. The specific patterns, distribution, and extent of skin necrosis remain poorly understood. The aim of this study is to provide new insights into skin necrosis following NLF injections by analyzing clinical cases and facial anatomy. METHODS: A retrospective review of patients with skin ischemia after NLF injections was conducted. Computed tomography angiography and anatomical dissections were performed on cadavers to study the facial artery. RESULTS: Twelve patients with skin ischemia were identified. Three patterns of skin ischemia were observed: Pattern I, NLF+Nose pattern (75%): Skin ischemia affects the nasolabial fold and the entire nose, with the alar, nasal tip, and dorsum being the most affected subunits. Pattern II, NLF+partial nose pattern (16.7%): Skin ischemia involves the nasolabial fold and the lower two-thirds of the nose, primarily affecting the nasal tip and alar, without extending beyond the rhinion. Pattern III, NLF+infraorbital area pattern (8.3%): Skin ischemia is observed in the nasolabial fold and infraorbital region, which may be attributed to the presence of a detoured facial artery. Anatomical studies revealed the course and branches of the facial artery, explaining the distribution of skin ischemia. The skin ischemia may be associated with the perforators of the superficial fat compartments. CONCLUSION: Skin ischemia following NLF injections can manifest in three distinct patterns, involving various facial regions. Understanding the anatomy of the facial artery and its branches is crucial for preventing and managing this complication. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .