Movement of the Syringe During Filler Aspiration: An Ultrasound Study.

In all cases, the aspiration and injecting maneuver is associated with micromovements of the needle tip, of a magnitude consistently significant relative to the typical size of facial vessels. Although needle tip movement is only a single factor limiting the usefulness of the aspiration test, the results of this study suggest that it is not advisable to rely only on aspiration as a method to prevent intravascular injection.