Objective: Delayed facial palsy has been reported following various types of otologic surgery. However, the exact characteristics of this disease have not been fully elucidated because of its low incidence. This study analyzed case series studies on delayed facial palsy to increase the sample size and outline credible disease characteristics.
Data sources: PubMed, Embase, and Cochrane Library databases were searched on October 10, 2018.
Study selection: Delayed facial palsy case series covered in English in which the intervention was typical tympanoplasty, mastoidectomy, stapedectomy, or cochlear implantation including a statement of sample size.
Data extraction: Evaluated according to the Joanna Briggs Institute Critical Appraisal Checklist for Case Series.
Data synthesis: Fourteen case series studies were included. Incidence rate, onset time, prognosis were evaluated with meta-analysis. Etiology and treatment were discussed with systematic review.
Conclusions: The overall incidence rate of delayed facial palsy after middle ear surgery was 0.65%; however, it differed depending on the type of surgery. The mean onset time of facial palsy was 8.47 ± 3.98 days after surgery, and 95.3% of the patients completely recovered. The disease seems to have multiple etiologies. Facial palsy occurring 2 to 20 days after surgery is suggested to be considered delayed facial palsy.