||Preauricular pits are shallow pits which appear to be due to a failure in the fusion of the primitive ear hillocks, or to a defective closure of the first branchial cleft. Preauricular pits are inherited by means of an autosomal dominant gene, with incomplete penetrance. They occur unilaterally in about 75% of cases and are more common in blacks, occurring in 5% of the black population.
The opening of a preauricular pit is characteristically located in or just in front of the anterior crus of the helix. The pits often discharge a cheesy substance, which consists of desquamated keratin debris.