Auditory canal or aural atresia is a congenital condition involving an abnormal development of the external auditory canal and outer ear. Typically, patients are affected in one ear but sometimes both ears can be affected. Other developmental abnormalities of the external and middle ear are common with aural atresia. Together, these abnormalities result in conductive hearing loss, a type of hearing loss stemming from the physical inability of sound to pass through the outer and/or middle ear. Patients with aural atresia typically have normal inner ears and auditory nerves.
Stenosis of the auditory canal is the term used to describe ear canal narrowing and is congenital or, occasionally, acquired. When congenital, it can be concurrent with aural atresia due to malformations of the external or middle ear. (Auditory canal stenosis is occasionally a result of chronic inflammation, radiation therapy, trauma to the ear, or poor healing of the ear canal post surgery.) One or both ears can be affected. Patients with stenosis of the auditory canal have a chance of developing cholesteatoma since the ear’s self-cleaning mechanism is affected.
Treatment of aural atresia and associated auditory canal stenosis may involve the use of amplification devices such as hearing aids, bone-conducting or bone-anchored hearing devices, or surgical correction.