Adverse Events Associated with Hyaluronic Acid Filler Injection for Non-Surgical Facial Aesthetics: A Systematic Review of High Level of Evidence Studies.

The article titled "Adverse Events Associated with Hyaluronic Acid Filler Injection for Non-surgical Facial Aesthetics: A Systematic Review of High Level of Evidence Studies" by Kyriazidis et al.in Aesthetic Plastic Surgery presents a systematic review focused on categorizing complications linked to hyaluronic acid (HA) dermal fillers. However, concerns arise about the methodologies employed in the reviewed studies. Precise knowledge of the active substance's properties is vital for treatment standardization. Gaining a comprehensive understanding of the key characteristics of the employed HA is of paramount importance to ascertain whether an association exists between these properties and the risk of complications. Understanding the rheological properties of HA, including viscosity, elasticity, and cohesiveness, is crucial for optimal facial filler selection. Acknowledging the authors' contributions, further analysis should encompass these factors.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 .