Effect of Glucocorticoids on Facial Nerve Injury

Objective: Examine the effect of both local and systemic dexamethasone administration on facial nerve return of function after complete axotomy and immediate microsurgical repair in a rat model. After nerve injury, an exaggerated neuro-inflammatory process may hinder regeneration. Therefore, our hypothesis is that glucocorticoid administration will improve nerve recovery.Method: A total of 74 Wistar rats underwent facial nerve axotomy with immediate neurorrhaphy. Blinded and randomized, rats were assigned a postoperative group: control (no therapy), systemic dexamethasone 0.5, 1, 5, or 10 mg/kg for 3 doses, or topical dexamethasone 2 or 4 mg/mL. Standardized facial assessments and nerve conduction studies (NCS) were performed.Results: At 8 weeks, rats receiving systemic dexamethasone at 1 and 5 mg/kg attained greater eye blink closure (P = .014 and P = .018, respectively) and vibrissae motion (P = .018 and P = .023, respectively) compared with controls. Systemic dexamethasone at 0.5 and 10 mg/kg had simil...