A congenital pit or sinus involving the ascending limb of the helix of the ear (fig. 1 a) or the preauricular region is of little importance unless it gives rise to an offensive discharge or forms a retention cyst (fig. 1 b). When infected, such a lesion is of considerable clinical significance, since drainage, extension, scarring and disfigurement are the common sequelae. Infection also may result in a secondary preauricular lesion, which so dominates the clinical picture that the underlying fistula itself may be overlooked entirely.
Differences in nomenclature and in methods of treatment and contradictory theories advanced to explain the origin of such pits and sinuses lend confusion to a study of the literature on this subject. These embryonic structures are known by a variety of names, such as "sinus preauricularis congenita," "branchial fistula in the external ear," "fistula auris congenita," "helical fistula" and "preauricular fistula."
Although these sinuses,
PASTORE PN, ERICH JB. CONGENITAL PREAURICULAR CYSTS AND FISTULAS. Arch Otolaryngol. 1942;36(1):120–125. doi:10.1001/archotol.1942.03760010130011