Microtia

congenital deformity where the pinna (external ear) is underdeveloped

Microtia meaning 'small ear' is a deformation of the outer ear. Over 90% of the time, only one ear is affected, but both ears can be affected. More boys are affected than girls. The right ear is more affected than the left. One in 1000 people have microtia. It can affect hearing. There are four grades of microtia:

  • Grade I: A slightly small ear with identifiable structures and a small but present external ear canal
  • Grade II: A partial or hemi-ear with a closed off ("stenotic") external ear canal producing a conductive hearing loss
  • Grade III: Absence of the external ear with a small peanut vestige structure and an absence of the external ear canal and ear drum
  • Grade IV: Absence of the total ear {"anotia")

Grade III is most common, and can be corrected by surgery.