Congenital Ear Abnormalities
Microtia and external auditory canal atresia (which causes conductive hearing loss) involve the external ear. These malformations, which frequently coexist, are often identified at or soon after birth. Occasionally, school-based screening tests identify a partially occluded external auditory canal in children with a normal pinna.
Low-set ears are ears positioned below where ears are typically positioned on the head. In low-set ears, the top of the pinna is positioned below the horizontal line connecting the outer corners of the eyes. This abnormality is associated with a number of genetic syndromes and often with developmental delays.
Ear pits and ear tags are minor anomalies typically located in front of the ear. Patients with these anomalies should be evaluated for hearing loss and for other congenital anomalies (eg, kidney anomalies with ear pits in branchio-oto-renal syndrome).
Hearing tests and CT of the temporal bone are necessary to evaluate possible additional bony malformations.
Treatment of ear abnormalities can include surgery and a bone-conduction hearing aid, depending on whether the malformation is unilateral or bilateral; whether it affects hearing, learning, and social development; and whether complications (eg, facial nerve involvement, cholesteatoma, otitis media) are present. Surgery may include pinna reconstruction and the creation of an external auditory canal, tympanic membrane, and ossicles.