Rapidly reversible total facial paralysis after lipofilling around facial nerve truncus

Autologous fat grafting is widely used for secondary contour refinement following head and neck reconstruction and is generally considered safe. However, irradiated reconstructed tissues exhibit fibrosis and reduced compliance, potentially predisposing patients to uncommon complications. Transient facial nerve paralysis following fat grafting has not previously been reported in an irradiated anterolateral thigh (ALT) free flap. A 57-year-old man underwent extensive oncologic resection for verrucous squamous cell carcinoma involving the temporal bone and parotid region, followed by ALT free flap reconstruction and adjuvant radiotherapy. After flap debulking and an initial lipofilling procedure, a second fat-grafting session (60 mL) was performed five months later for residual preauricular contour deformity. Immediately after surgery, the patient developed House-Brackmann grade V facial paralysis. Systemic methylprednisolone was initiated at 64 mg/day and tapered over five days. Facial function improved rapidly, with complete recovery within 36 hours and no residual deficit. Given the close temporal relationship to fat grafting and rapid recovery, transient pressure-related neuropraxia within the irradiated fibrotic tissue bed was considered a plausible mechanism; however, this remains hypothetical without objective evidence of nerve compression, edema, or ischemia. To our knowledge, this is the first reported case of rapidly reversible total facial paralysis following autologous fat grafting in an irradiated ALT free flap. Reduced tissue compliance secondary to radiation-induced fibrosis may contribute to transient nerve dysfunction. Awareness of this potential complication and cautious, low-pressure injection may be important when performing fat grafting near major nerve structures in irradiated reconstructive fields.