Prenatal diagnosis of low-set ears with asymmetrical microtia in the first trimester

Abstract

Initially, the external ears are in the lower neck region, but with the development of the mandible, they ascend to the side of the head at the level of the eyes. Low-set ear is one of the features often associated with genetic disorders, and external ear defects are significant because they are often associated with other malformations. The problem may occur as a symmetrical condition but an asymmetrical condition is not rare, in which one side of the face is maldeveloped. This defect varies in severity; however, it always includes maldevelopment of the ear and the mandible. Recent advanced 3D HDlive ultrasound enables us to demonstrate fetal external ear position and development even as early as in the first trimester. The picture of the month clearly demonstrated low-set ears with asymmetrical development of the ear and face at 12 weeks of gestation. Early detection of ear abnormality leads to further genetic and morphologic investigation as well as to proper management and counseling.