Needle Microcores: Can They Pose an Occlusive Threat with Nonparticulate Injections?

Summary: The incidence of vascular occlusion injuries has risen substantially along with the increasing popularity of cosmetic injectables. Among these occurrences, instances of soft-tissue ischemic events following the injection of nonparticulate solutions, such as botulinum, represent an enigmatic etiology that has yet to be fully understood. One hypothesized mechanism of injury underlying these events relates to the accidental capture and intravascular ejection of needle microcores, defined as submillimeter tissue fragments trapped by the beveled lumen of a needle during conventional injections. To test this hypothesis, the authors conducted a cytologic evaluation of dermal remnants incidentally captured by 31-G tuberculin needles following repeated injections into postrhytidectomy skin fragments. Their findings revealed the presence of dermal tissue microcores ranging from 100 to 275 μm in diameter with an overall microcoring incidence of 0.7%. These findings confirm the ability of ultrafine needles, commonly used in botulinum injections, to produce tissue microcores that may serve as causative agents of vascular occlusion with nonparticulate solutions. Awareness of this mechanism of injury may be of benefit in the early recognition and management of these rare occurrences.

Clinical Question/level Of Evidence: Therapeutic, V.