Study Finds Neofilera Dermal Filler Presents Lower Embolic Risk at Lower Injection Volumes in Rabbit Model
A preclinical study published on bioRxiv assessed the arterial embolism risk of Neofilera, a carboxymethyl cellulose and polylactic acid microsphere filler, by injecting it into rabbit ear arteries at varying volumes and dilutions. At 0.1 mL, the filler dispersed within minutes and did not cause significant tissue necrosis, while 0.2 mL injections — even when diluted — were associated with increased vascular occlusion. The findings suggest that injection volume is a critical determinant of embolic risk for this filler formulation, with potential implications for clinical safety guidelines.
Researchers evaluated the embolic risk of Neofilera, a dermal filler combining carboxymethyl cellulose and polylactic acid microspheres, using a rabbit central auricular artery model. Animals received intra-arterial injections of either 0.1 mL or 0.2 mL of Neofilera at three dilution ratios (1:5, 1:10, and 1:15) or normal saline as a control. Transparent emboli were assessed immediately post-injection, and tissue necrosis and histopathological changes were evaluated on days 1 and 7. At the 0.1 mL volume, the filler dispersed rapidly and did not produce significant tissue necrosis at either time point across all dilution groups. However, injections of 0.2 mL were associated with a notably higher incidence of vascular occlusion regardless of dilution level. The study concludes that Neofilera carries a comparatively lower embolic risk at lower volumes, but that higher volumes substantially elevate the likelihood of serious vascular complications. These results underscore the importance of volume control in aesthetic filler procedures to minimize the risk of arterial embolism.
What's missing
The study is a preprint and has not yet undergone peer review, so findings should be interpreted with caution. Key limitations include the use of an animal model (rabbit ear artery), which may not fully replicate human facial vascular anatomy or clinical injection techniques. The study does not compare Neofilera's embolic risk directly against other commercially available fillers, limiting conclusions about relative safety. Long-term outcomes beyond day 7 and the reversibility of observed vascular occlusions are not reported.
What different sources said
- bioRxivCenter
Risk Assessment of Arterial Embolism from Neofilera(R) Filler in Rabbits
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