Related Experiment Video
Updated: Dec 23, 2025
A New Ex Vivo Model for the Evaluation of Endoscopic Submucosal Injection Material Performance
Published on: October 19, 2018
Utility of Preinjection Aspiration for Hyaluronic Fillers: A Novel In Vivo Human Evaluation
Jordan V Wang1, Ezra Hazan1, Georgette Hattier1
16559 Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA, USA.
Background:
Hyaluronic acid (HA) fillers have increased in popularity. While complications are rare, practitioners should focus on their prevention. Preinjection aspiration remains controversial as an effective safety checkpoint.
Objectives:
Our study investigated the utility of preinjection aspiration as a safety checkpoint for HA fillers through comparison of physiochemical and rheological properties in a novel in vivo human model.
Methods:
An in vivo human model consisted of a cannula inserted into a peripheral vein. Preinjection aspiration was evaluated using syringes of 10 commonly used HA fillers. The time required to visualize a flash was recorded.
Results:
Using a multivariable regression model, needle gauge, HA concentration, elastic modulus (G'), viscous modulus (G″), and complex modulus (G*) had significant relationships with time to flash, whereas pullback volume did not. However, when comparing pullback volume using a more appropriate paired analysis, 0.5 cc pullback volume had a significantly decreased time to flash than 0.2 cc.
Conclusions:
Preinjection aspiration for HA fillers has utility as a safety checkpoint. The times to visualize flashback decreased when using a human peripheral vein model compared to a previous in vitro model, suggesting that there may be real-time clinical utility of preinjection aspiration. Waiting times to visualize flashback may be affected by physiochemical and rheological properties. Additional studies would help to validate our results.
