[Branchiogenic preauricular fistulae]

Seventeen patients with dimples, fistulae and cysts in the region of the cheek and the preauricular field are reported. All are located in the neighborhood of the dorsal end of the first visceral arch. Both the fistulae of the ascending helix and the upper preauricular fistulae must be regarded as relics of the dorsal end of the first branchial cleft. This interpretation supports the theory of Wood-Jones and I-Chuan according to which the tragus is formed from the material of the mandibular arch, and the remaining part of the auricle from the mesoderm of the second visceral arch. Similar anomalies in the neighborhood of the angle of the mouth, the extraoral opening of an accessory duct of Stensen and the inferior preauricular fistula are sufficiently explained by the incomplete closure or tearing of the embryonal oral aperture.