Rates of Positive Aspiration Prior to Facial Hyaluronic Acid Filler Injections: Outcomes of a Multicenter, Cross-sectional Study.

[BACKGROUND] Before administering hyaluronic acid (HA) fillers, aspiration can be performed as a safety measure to determine whether the needle tip is located within a vascular structure. However, the efficacy and utility of aspiration have been questioned. A real-world evaluation would contribute to understanding how this technique is used globally.

[OBJECTIVES] The aim of this study was to determine the incidence (as a percentage) of positive pretreatment aspiration in a real-world setting.

[METHODS] An observational study with a cross-sectional design was conducted to evaluate the incidence of positive aspiration before facial HA injections. Investigators from 14 aesthetic/dermatologic practices in 9 different countries participated in the study. The active data collection period was 12 weeks. Data of all patients presenting to the participating clinics during the active data-collection phase, and who underwent HA injections to any region of the face, were included. The aspiration technique included slowly pulling back on the plunger of the syringe and holding it back for a minimum of 5 seconds, to allow proper time for flashback.

[RESULTS] Data from 5106 aspirations performed in 1007 individual patients were collected. In total, 35 cases (0.69%) of positive aspiration were recorded. However, there were significant differences in the incidence reported by investigators (range, 0%-6.72%).

[CONCLUSIONS] The results of this study can be used to assess the utility of pretreatment aspiration as a safety measure before performing HA filler injections, and contribute to the understanding of the effect of various factors on positive preinjection aspiration under clinical conditions.