title: Anatomic variations and anomalies involving the facial canal.
abstract: Congenital bony dehiscences in the facial canal result from incomplete closure during development and are observed in approximately 55% of temporal bones. Anomalies involving the facial canal frequently are encountered in malformations of the temporal bone. These anomalies include aberrations of the course of one or all of the segments of the canal; abnormal relation to the oval and round window; bifurcations and trifurcations of the nerve; and associations with dysplasia of the stapes, oval window, external ear canal, and auricle. Rarely, the facial nerve may be hypoplastic or totally absent. Two abnormal vessels occasionally may accompany the facial nerve in the Fallopian canal: a persistent stapedial artery and a persistent lateral capital vein.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine and Hospital, Baltimore, Maryland.
authors.forename: G T
authors.initials: GT
authors.lastname: Nager
authors.forename: B
authors.initials: B
authors.lastname: Proctor
mesh_terms: D002814:Chorda Tympani Nerve / Q000002:abnormalities; D007758:Ear, Inner / Q000002:abnormalities / Q000098:blood supply; D004432:Ear, Middle / Q000002:abnormalities / Q000098:blood supply; D005154:Facial Nerve / Q000002:abnormalities* / Q000601:surgery; D006801:Humans; D008416:Mastoid / Q000002:abnormalities / Q000098:blood supply; D011300:Preoperative Care; D012665:Semicircular Canals / Q000002:abnormalities / Q000098:blood supply; D013701:Temporal Bone / Q000473:pathology