RESUMEN
AestheFill is a biostimulator based on poly-D,L-lactic acid. It is supplied as lyophilized powders and is referred to as a versatile biostimulator. According to the amount of water added, the suspensions can be vary in thickness which can be divided into four groups for different indications: the thickest suspension (D1.5-3) for nose or chin augmentation, thick suspension (D3-6) for deep wrinkle correction, thin suspension (D6-12) for shallow wrinkle correction, and super-thin suspension (D12-24) for skin rejuvenation. However, practitioners may be confused about which filler thickness, injection layer, method, and amount should be chosen for their patients. Biostimulators tend to form non-inflammatory nodules if technical mishaps occur during injection. Based on 10 years of AestheFill injection experience, the authors proposed the AestheCode system for the safe and effective injection of AestheFill.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 .
RESUMEN
The occurrence of 'retrograde flow along the cannula/needle tract' during filler injections has not been extensively addressed in the existing literature, possibly because it is often imperceptible unless the injection is conducted at a superficial layer. In our experience with poly-D,L-lactic acid filler for lower eyelid injections, we have observed and documented this phenomenon through the skin. This article aims to elucidate and illustrate the retrograde flow phenomenon and discuss the factors influencing it.