Microtia is a congenital deformity in which the pinna is very small and underdeveloped. This abnormality can be unilateral, affecting only one ear, or bilateral, affecting both ears. Unilateral microtia is most common, in which the right ear is affected more frequently than the left ear. A genetic disturbance results in microtia of the pinna. Many cases of microtia are categorized as idiopathic or of an unknown etiology. Occurring in 1 to 5,000-20,000 births, this deformity is more frequently seen in males. (Fuller, Pimentel & Peregoy, 2011, 330). Microtia causes varying degrees of hearing loss and major cosmetic problems. Population
In a study, “Melnick and Myranthopoulos reviewed auricular deformities and associated anomalies in a series of 56,000 pregnancies in an ethnically diverse population (Caucasian 46%, African American 46%, Latino 8%), commenting on the incidence of anomalies and the embryogenesis and etiopathology of the varying deformities” (Lin, 2011). They found that microtia occurred in every 3 in 10,000 births. Microtia occurs in 1 per 900 to 1200 Navjo children and 1 in 4000 Japanese births (Fuller, Pimentel & Peregoy, 2011, 330). Time of Onset
Microtia is a congenital deformity, meaning that it is present at birth. Receiving genes from both parents during development, microtia results from a defective gene in the early development stage of ear development. Since microtia occurs in utero, there is no easy fix for this abnormality until the child is ready for surgery to recreate the outer ear. Etiology
Hereditary factors and vascular accidents in utero are both factors in the etiology of microtia. Familial patterns are reminiscent that microtia is a result of multifactoral inheritance, including maternal rubella during the first trimester of pregnancy. Microtia occurs when there is a problem with the development of the ear when a baby is still an embryo. Occasionally occurring due to an inherited fault, microtia...