Supplementary Material for: Severe Periocular Inflammatory Reaction Mimicking Necrotizing Fasciitis Following Hyaluronic Acid Microinjections: A Case Report and Literature Review

Introduction Hyaluronic acid (HA) fillers are widely utilized in aesthetic medicine for facial rejuvenation, including in the periocular region. Although generally considered safe, severe inflammatory responses can occur. This report describes a case of a 42-year-old woman who developed a significant periocular reaction following HA microinjections, clinically resembling necrotizing fasciitis. Case Presentation The patient, with no significant medical or ophthalmic history, presented to the emergency department with acute periocular swelling, redness, and inability to open her right eye three hours after HA microinjections. Clinical examination revealed marked periorbital edema, chemosis, and restricted ocular motility in the right eye. The severity of the presentation initially suggested necrotizing fasciitis. A CT scan indicated preseptal cellulitis without post-septal involvement. Treatment with intravenous antibiotics, systemic corticosteroids, antihistamines, and topical therapies led to significant improvement. Conclusion This case highlights the need to recognize severe inflammatory reactions following periocular HA injections, which may mimic life-threatening conditions. Timely intervention and systematic evaluation are essential for achieving favorable outcomes.