The combination of platelet‐rich plasma with botulinum toxin A in the treatment of hyaluronic acid embolic cutaneous necrosis and alopecia

Dear Editor, Patients with hyaluronic acid (HA) injection into temples are at a high risk for vascular occlusion. It may contribute to the tissue ischemia, followed by skin necrosis and alopecia. Timely injection of hyaluronidase was effective to reverse vascular impairment and minimize skin necrosis. However, the consequences of inadequate management of arterial occlusion are serious and could lead to increased incidence of skin necrosis. Here, we present a case occurred scalp necrosis and secondary alopecia despite high dose hyaluronidase being given. After combination platelet-rich plasma (PRP) with botulinum toxin A (BTXA), the wound gradually healed and the hair-growth gradually recovered (Data S1). A 32-year-old female had vascular occlusion after receiving 2.0 ml HA fillers (brand not known) into the temple. She was treated with hyaluronidase, which was inadequately effective. On Day 3, she presented to our outpatient clinic. The temple skin symptoms improved after 3000 units of hyaluronidase. Then she was prescribed antibiotics, vasodilator therapy, and hyperbaric oxygen therapy in the following days. However, after 10 days, right frontotemporal scalp necrosis developed, gradually followed by alopecia. Subsequently, antibacterial medical dressings and recombinant bovine basic fibroblast growth factor gel were applied, but the healing process is slow. On Day 89, the patient was treated with subcutaneous injection of 11.0 ml PRP with 30 units of BTXA (Figure 1A). The wound healed after 10 days, and no adverse events occurred. The patient received two treatments on Day 121 (10.0 ml PRP with 30 units of BTXA) and Day 148 (8.6 ml PRP). On Day 176, hair growth gradually recovered except for a 2 2 cm permanent cicatricial alopecia (Figure 1B–D). HA-induced alopecia may be secondary to vascular occlusion in branches of superficial temporal artery, and recovery of alopecia might depend on the restoration of nutrient and blood supply. As for the scalp necrosis, unhealed wound and inflammatory response could impede hair regeneration. PRP may accelerate wound healing, and provide enough growth factors for hair follicle regrowth. It may also