What are the risk factors for facial nerve palsy after benign parotid surgery?

Introduction: Post-operative facial palsy is the most important potential complication of parotid surgery for benign lesions. The published prevalence of facial weakness is up to 57 per cent for temporary weakness and up to 7 per cent for permanent weakness. We aimed to identify potential risk factors for post-operative facial palsy. Materials and methods: One hundred and fifty patients who had undergone parotid surgery for benign disease were retrospectively reviewed. Tumour factors (size, location and histopathology), patient factors (age and sex) and operative factors (operation, surgeon grade, surgeon specialty and use of intra-operative facial nerve monitoring) were all analysed for significant associations with post-operative facial palsy. Results and analysis: The overall incidence of facial palsy was 26.7 per cent for temporary weakness and 2.6 per cent for permanent weakness. The associations between facial palsy and all the above factors were analysed using Pearson's chi-square test and found to be non-significant. Conclusion: These outcomes compare favourably with the literature. No significant risk factors were identified, suggesting that atraumatic, meticulous surgical technique is still the most important factor affecting post-operative facial palsy