Introduction:
Head and neck development involves morphogenesis with contributions from the ectoderm, mesoderm, and endoderm layers, as well as neural crest cells. During the fourth to sixth weeks of gestation, mesenchymal proliferations known as hillocks of His arise from the first and second pharyngeal arches. Under the influence of various molecular signals, these hillocks undergo differentiation to give rise to structures of the external ear, including the tragus, which arises from the first of the six hillocks.1
Early in embryonic development, the preauricular sulcus emerges as a remnant of the first branchial arch which initially appears as a skin groove around the developing ear. As development continues, the preauricular sulcus extends from its origin near the developing ear towards the ventral aspect of the neck. Along its path, it passes through the first pharyngeal cleft, eventually giving rise to structures that eventually form part of the oropharynx. Abnormalities in this migration process can occur, leading to the presence of ectopic tissue, such as an accessory tragus, within the oropharynx.2,3
In this report, we discuss the case of an accessory tragus incidentally identified in the oropharynx of a 20-year-old female presenting with left-sided conductive hearing loss.