Hyaluronic Acid Filler Migration

Soft tissue filler injections continue to grow in popularity as a method of facial rejuvenation, including volume restoration and contour enhancement. Many different hyaluronic acid (HA)-based fillers are available on the market and differ in terms of their physical and chemical properties, which results in families of fillers (e.g., Non-Animal Stabilized Hyaluronic Acid - NASHA vs. Optimal Balance Technology - OBT) with different tissue integration patterns. It has been proposed that the properties of fillers significantly influences their tendency to migrate. More specifically, thick fillers may be less prone to migration compared to fluid fillers. However, a detailed knowledge of facial anatomy, safer injection techniques, and careful product selection based on filler qualities may be preventive measures for filler migration. The goal of this study is to describe the short and intermediate-term product distribution/integration patterns of NASHA and OBT-based fillers, and to evaluate the evidence (if any) of filler migration from the intended site of injection.