Embryology of Ear (General)

Synonyms

Developmental anatomy; Embryology; Ontogeny

Definition

Embryologic development from the primitive fetus to a fully functioning organ system

Basic Characteristics

Introduction

The ear is composed of three anatomic divisions, each with unique embryologic origins: (1) the external ear, which consists of the auricle (pinna), the external acoustic meatus and canal, and the external layer of the tympanic membrane; (2) the middle ear, an air-containing space lined by respiratory epithelium housing the three ossicles and containing the internal layer of the tympanic membrane; and (3) the inner ear, which includes the bony and membranous labyrinth and cochlea. Because inner ear development occurs independent of that of the middle and external ears, congenital sensorineural hearing loss typically occurs in the presence of a normal outer and middle ear, while congenital defects of the middle and/or external ear most often occur in the setting of a structurally and functionally normal...