Agarose Gel as an Injectable Filler Significantly Reduced the Risk of Rabbit Retinal Artery Embolism Compared to Hyaluronic Acid.

Abstract

BACKGROUND: Vascular embolism is a common complication associated with the use of injectable fillers. Agarose gel, a novel filler, may have a lower risk of embolism. However, there are few studies investigated the embolism rate of agarose gel and other fillers. This study aims to compare the risk of rabbit retinal artery embolism caused by hyaluronic acid or agarose gel in vivo, as well as their dissolution characteristics in vitro. METHODS: The study used a rabbit model of retinal artery embolism. Agarose gel or hyaluronic acid was injected into the carotid artery at doses of 0.1, 0.2, and 0.3 mL (each group n = 6). A vascular clamp was used to redirect the material toward the internal carotid artery and retinal artery. The ocular fundus was observed before and after injection to assess embolism. In the dissolution experiment, both materials were dissolved in either saline or hyaluronidase, and their dissolution rate was recorded and quantified. RESULTS: We found that the embolism rate was significantly higher in the hyaluronic acid group especially in the HAgroup (83.3%) with no embolism observed for agarose gel. As the injection dose increased, the embolism rate in the HA groups increased. Agarose gel can be dissolved in saline and dissolved much faster (about 180s) compared to hyaluronic acid (about 456s) when treated with hyaluronidase (p < 0.001). CONCLUSION: In rabbit retinal artery embolism model, agarose gel was a safe injectable filler with a low risk of vascular embolism in vivo and fast dissolution rate in vitro. 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 &#xa0; www.springer.com/00266 .