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Efficacy of Percutaneous Superficial Temporal Arterial Hyaluronidase Injection for Hyaluronic Acid Filler-Induced Necrosis of Frontotemporal Skin and/or The Ipsilateral Scalp With Subsequent Alopecia.

BACKGROUND
Necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia after hyaluronic acid (HA) filler injection into the temple are rare and newly reported complications, with superficial temporal artery (STA) embolization suspected as the major pathological mechanism. The main treatment currently is intralesional hyaluronidase (HAase) injection, but the effectiveness of percutaneous superficial temporal arterial HAase injection still lacks consensus.


OBJECTIVES
The aim of this study was to investigate the effectiveness of superficial temporal arterial HAase injection in dissolving HA filler-induced necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia.


METHODS
In this study, 5 recent clinical cases with necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia after HA filler injection into the temple were analyzed retrospectively. The patients underwent HAase injection via STA combined with adjunctive treatments, and the clinical progress was observed.


RESULTS
The significant improvement was observed in terms of necrosis of frontotemporal skin and the ipsilateral scalp after treatment and the patients were relieved of their clinical symptoms. Alopecia occurred approximately 1 to 2 weeks after HA filler injection, and the well-defined alopecia areas were formed about 15 to 20 days after HAase injection. Patients were subsequently followed for 3 to 6 months. During follow-up, the skin lesions of all patients were restored to near normal appearance. Hair regrowth was observed 2 to 3 months after HAase treatment and the hair density nearly reached the normal level 3 to 4 months later.


CONCLUSION
Percutaneous superficial temporal arterial HAase injection is an effective treatment option for HA filler-induced necrosis of frontotemporal skin and/or the ipsilateral scalp with subsequent alopecia.