Objectives: To assess the ability of postoperative electroneuronography (ENoG) and electromyography (EMG) to predict clinical facial function at one year postoperatively in patients with facial paralysis and an intact facial nerve after cerebellopontine angle surgery.
Study design: Prospective, non-randomized, uncontrolled clinical trial.
Setting: Outpatient, at tertiary care hospital.
Patients: Primary eligibility criteria include: (1) cerebellopontine angle (CPA) surgery with anatomical preservation of facial nerve, (2) complete facial nerve paralysis, and (3) one year follow-up.
Main outcome measures: ENoG and EMG at 1 and 3 months postoperatively, House-Brackmann facial nerve grade at one-year postoperatively.
Results: The Kendall coefficient of rank correlation demonstrated that the 1 and 3 month postoperative ENoG data were significant predictors of ultimate facial nerve outcome. Tracking multiple ENoG examinations in a single patient, over time was of little predictive value. EMG was a poor predictor of facial nerve outcome. In general patients with delayed facial nerve paralysis had better ultimate facial function than patients with immediate paralysis.
Conclusions: Postoperative ENoG, but not EMG was a statistically significant predictor of ultimate facial nerve outcome after CPA surgery. Patients with delayed facial paralysis had better outcomes than those with immediate facial paralysis.