Embryology and anomalies of the external ear

Abstract

The embryology of the ear provides insight into the fundamentals of surgical reconstruction and support to the concepts that guide our approaches to complete excision of redundant elements. The external ear develops from ectodermal and mesodermal elements of the first and second branchial arches. Anomalies of the ear may therefore reflect abnormal development of other first and second arch structures. Accurate recognition of syndromic ear anomalies also allows for the potential detection of other systemic conditions. The authors discuss the embryology of the auricle; external auditory canal; dysmorphogenesis of the auricle; auricular pits, cysts, and sinuses; microtia; anomalies of the antihelical cartilage; protruding ears; cryptotia, anomalies of the external auditory canal; and syndromic ear anomalies.