Atypical Location of the Facial Nerve in a Patient with a First Branchial Cleft Fistula.

First branchial cleft anomalies are rare. Its estimated incidence is one in 100,000. Clinically, patients present with recurrent otorrhea, periauricular swelling, and/or flowing fistula in the neck. Surgical removal of the tract is considered the best treatment option for the first branchial cleft fistula. Due to the close relationship between the fistula tract and the facial nerve branches, facial nerve injury is one of the not uncommon complications of this surgery. Different variations in the relationship between the fistula tract and the facial nerve trunk and its branches have been mentioned in the literature. In this study, we presented the case of an atypical course of the facial nerve in a nine-year-old pediatric patient who underwent first branchial cleft fistula surgery, and discussed the importance of anatomic variations and measures to be taken to prevent facial nerve injury.