The outer most portion of the ear encompassing the pinna and ear canal.The pinna – the part of the “ear” that we see on each side of our heads – is made of cartilage and soft tissue so that it keeps a particular shape but is also flexible. The pinna serves as a collector of sound vibrations around us and guides the vibrations into the ear canal. It helps us decide the direction and source of sound.
Developmental abnormalities of the outer ear include microtia (also called small ear) and aural atresia. Microtia refers to an auricle that has not fully developed. There are varying degrees of microtia depending on how well developed the auricle is. The degree of auricle development can range from simply a small ear with all the proper cartilage (grade I) to a small “nubbin” or peanut ear where there is no cartilage, just a mound of skin and soft tissue (grade III). Rarely, people are born without an auricle, a condition called anotia. A plastic surgeon skilled in microtia repair can often rebuild the ear to a very favorable appearance using a prosthesis, the person’s own rib cartilage, or an implant.
Microtia is often accompanied by aural atresia, which is failure of the ear canal to open. This absence of the ear canal is also usually associated with underdevelopment of the middle ear and middle ear bones (hammer, anvil, and stirrup). Children have hearing loss because the sound energy is not efficiently carried, or conducted, into the middle ear. In some children, surgery can be done to open the ear canal, build an eardrum, and restore the natural sound-conducting pathway of the ear canal and middle ear to the healthy inner ear.
