Sinus, Preauricular

Synonyms

Preauricular cleft; Preauricular cyst; Preauricular fistula; Preauricular fistulous tract; (Spectrum of) first branchial cleft anomalies

Definition

Preauricular sinuses, cysts, and fistulas are caused by incomplete closure of the first branchial cleft. The so-called first branchial cleft anomalies spectrum therefore involves broad range of different painless cysts, and fistulas, or draining sinus tracts on skin or neck. They result from incomplete fusion of the first and second branchial arches, with persistence of the ventral component of the first branchial cleft. The most commonly used classification of the first branchial cleft anomalies is the Work and Proctor type I: ectodermal origin with close proximity to the external auditory canal, and type II: ectodermal elements of the first branchial cleft and mesodermal components of the first and second branchial arches, which is more medially and inferiorly located.

Painless cystic lesions or draining sinus tracts are the most...