Asymptomatic post-auricular cystic mass in a healthy 3 year-old boy. Axial CT scan picture shows an ovoid cyst medial to the concha and protruding slightly into the post-auricular sulcus.
The cyst was excised and the defect was repaired primarily. There were no connections with the external auditory canal or middle ear. The specimen is shown on the right.
FIRST BRANCHIAL CLEFT
Cystic lesions near or around the external auditory canal are believed to represent first branchial cleft duplication anomalies, classified by Work as Type I or Type II.
Tracts arising from (Type I) or paralleling (Type II) the external auditory canal can lead to a cystic cavity, which will become recurrently infected and often drain in or near the ear.
Other anomalies associated with faulty first cleft development include: pits of the lower lip; clefts of the middle chin and ear lobe; preauricular sinuses and tags; cervical tags and dermoid cysts; atretic, stenosed or malformed external auditory canals; and double or congenitally perforated T.M. Sinus tracts paralleling the EAC, or arising from it, are also well recognized first branchial cleft anomalies.