Sialocele following excision of delayed-onset inflamed facial fat graft: A case report.

[RATIONALE] Autologous fat grafting is a widely used technique for facial contour restoration and is generally considered safe. Nevertheless, delayed inflammatory reactions may occur and, in rare instances, require surgical intervention. Excision of the inflamed graft in the midface region carries a potential risk of intraoperative injury to critical structures, including the facial nerve and parotid gland.

[PATIENT CONCERNS] 24-year-old woman presented with progressive swelling and tenderness of the left cheek 4 years after autologous facial fat grafting.

[DIAGNOSIS] Magnetic resonance imaging revealed mixed fat necrosis and fluid collection beneath the superficial musculoaponeurotic system (sub-SMAS) plane, with extension into the masseter muscle.

[INTERVENTIONS] As the symptoms did not improve with antibiotics and anti-inflammatory medications, surgical excision was performed. Histopathological examination revealed benign fibroadipose tissue with mild chronic inflammation and fat necrosis. Following partial excision of the inflamed graft, a postoperative sialocele developed, raising suspicion of parotid gland injury. Conservative management with anticholinergic agents and intraparotid botulinum toxin injection was initiated.

[OUTCOMES] The sialocele resolved without the need for surgical repair. At the 6-month follow-up, no recurrence was observed.

[LESSONS] Delayed inflammation may develop after autologous fat grafting, occasionally necessitating surgical intervention. Surgical excision in the deep midface region poses a risk of intraoperative parotid injury. Awareness of this potential complication is important, and conservative management can often effectively treat parotid leakage or sialocele without further surgery in selected cases.