Delayed Foreign Body Granulomas in the Orofacial Region after Hyaluronic Acid Injection

Objective: To evaluate and analyse granulomatous reaction caused by intradermal injections with hyaluronic acid (HA) fillers in the orofacial region. Methods: A retrospective review of 11 cases of foreign body granulomas caused by HA fillers was performed. Demographic data, clinical symptoms, imaging features, treatments, pathology results, history of facial cosmetic procedures and prognosis were reviewed. Results: Most of the cases appeared as painless palpable nodules with no significant growth, located in the cheeks, chin, lips or temples. The nodules were excised, and pathological examination revealed amorphous basophilic material surrounded by foreign body giant cells and macrophages. No patient's clinical and pathological diagnosis was linked to HA during the first appointment. During follow-up, all patients admitted that they had received dermal filler injections from 3 to 10 years previously. Most of the patients had a favourable prognosis; one patient complained of facial asymmetry and another reported mild pain in the upper lip after surgery. Conclusion: The increase in the number of cases showing delayed complications caused by HA fillers merits closer clinical attention. A thorough understanding of the patient's medical history and biopsy specimen are necessary to make a definite diagnosis and offer appropriate treatment.