A Histopathologic Diagnosis of Vascular Occlusion After Injection of Hyaluronic Acid Filler: Findings of Intravascular Foreign Body and Skin Necrosis.

[UNLABELLED] Before injecting hyaluronic acid (HA) filler into high-risk zones of the face, considerable caution must be exercised, including careful selection of the most appropriate filler, volume, and injection technique. Rare but severe adverse events have occurred during and after injection of HA filler in or around the periorbital region, such as skin necrosis and blindness. In the present case, involving a 57-year-old woman, approximately 0.1 mL of HA was injected into each side of the glabella to minimize wrinkles. The filler was injected into the dermis, utilizing the linear threading method. Proper care and caution were exercised before and during the procedure. Two days later, purple discoloration and erythema were observed in the left glabellar zone and forehead. A biopsy specimen was obtained and, based on histopathologic examination, frontal skin necrosis secondary to vascular occlusion was diagnosed. The likely cause and mechanism of the embolism will be discussed. To the author's knowledge, histopathologic findings of an intravascular remnant after injection of HA appear to be rare.

[LEVEL OF EVIDENCE] 5.