Microtia is a congenital anomaly of external ear (pinna) that ranges from mild structural abnormalities to complete absence of ear. When an external ear is absence, it is referred to as anotia. Microtia may occurs as an isolated deformity although it can also present itself as part of a spectrum of other deformities, either minor or major such as hemifacial microsomia, Goldenhar syndrome and Treacher-Collins syndrome. Most patients with the most severe form of microtia also lack an external auditory canal, also known as “atresia”, that often require treatment for hearing impairment and surgical ear reconstruction.
The reported prevalence of microtia varies among regions, and it is considered to be higher in Hispanics, Asians, Native Americans, and Andeans. The incidence of microtia is reported to be 1 in 8,000 – 10,000 births. Microtia can affect one side only (unilateral) or both sides (bilateral). Microtia occurs more commonly in males and on the right side. Approximately 10 percent may occur on both sides.